REQUEST FOR AFS RESEARCH FUNDS

PROJECT Date: August 7, 2019

Project Title: Effect of Ceramic Sand on Cast Iron Mechanical Properties

Principal Investigator: Dr. Scott R. Giese

PI Company/Organization: University of Northern Iowa

DIVISION SPONSORSHIP Sponsoring Committee & Division: Cast Iron Research Committee

Division Approval Communication Submitted for Proposal Yes No

QUAD CHART

Technical Problem Proposed Solution • Further understanding in use of ceramic • Cooling curve analysis of iron and thermal aggregates to addressed OSHA Silica Rule. diffusivity measurement will be performed. • industry does not know solidification • Class 30 gray iron and 80-55-06 ductile iron behavior impact of ceramic aggregate compare using 3:1 and 1:1 sand ratios will be to silica sand. poured for baseline silica sand and ceramic • experiments are proposed to measure media in green sand and air-set molds. the thermal physical properties of ceramic • Database can be developed for AFS community aggregates and their influence on to assess thermal impact when changing silica microstructure and mechanical properties for sand to a ceramic aggregate gray and ductile iron. • Microstructural analysis and mechanical properties determination will be performed and compared between silica sand and ceramic aggregate.

Research Team Proposal Cost & Timeline • Principal Investigator: Dr. Scott R. Giese, FEF • Total project cost = $122,075 Key Professor, University of Northern Iowa • In-kind contributions. • Co-Investigator: Sairam Ravi, Metal Casting • Project Duration: 10 months Center Project Manager, University of Northern Iowa • AFS Cast Iron Division and Ductile Iron Society • Steering Committee Chair: Brandon Reneau (Caterpillar) • Steering Committee Members: Matt Meyer (Kohler), Liz Median (Neenah Foundry)

PROPOSAL

1. Technical Problem / Current State of Technology. Due to the OSHA Silica Rule under enforcement in the foundry industry today, one scenario that many are considering is a change from silica sand, used in most foundries today, to a ceramic sand/media to alleviate the issue. There are many questions associated with this change, but one that is of primary importance is understanding the change, if any, in microstructure and the associated mechanical properties that might accompany the use of the ceramic sand/media. The American Foundry Society recently funded two research projects (https://www.afsinc.org/news/2018/03/28/afs-research-moving-industry-forward) investigating the use of ceramic molding aggregates, mostly focused on the substitution of this aggregate in clay-bonded green sand molding operations. The primary objective of the investigations addressed foundry concerns in casting surface, surface defects (in terms of metal penetration and veining), attrition losses, and sand reclamation. The Cast Iron Research Committee has initiated a research program exploring the influence of ceramic aggregates leading to changes in solidification behaviors affecting the microstructure, mechanical properties, and design for gray and ductile iron castings. Presently information is not available for the foundry industry for them to understand how thermal physical characteristics can influence subtle casting design and metallurgical changes leading to potentially costing tooling alterations. 2. Proposed Solution; Objectives, Deliverables, and Milestones.

TASK & DURATION (MOS) DELIVERABLE OR MILESTONE Task 1.1 – Develop Patterns for Air-Set Design Step Block using casting simulation tools to Molding (2 months) achieve quiescent filling and sound castings for class 30 gray iron and 80-55-06 ductile iron using baseline silica sand. Build 4 patterns for 3:1 and 1:1 sand ratios for class 30 gray iron and 80-55-06 ductile iron using baseline silica sand. Patterns will be designed for green sand and air-set molding operations. Task 1.2 – Molding and Pouring Operation Produce and configure thermocouples for data collection in for Air-Set Molding (1 month) phenolic urethane no-bake binder. Pour castings 3:1 and 1:1 sand ratios for class 30 gray iron and 80- 55-06 ductile iron using baseline silica sand and ceramic media. Determine thermal diffusivity, heat capacity, temperature dependent density, and thermal conductivity values for baseline silica sand and ceramic media. Perform cooling curve analysis for baseline silica sand and ceramic media for Task 1.3. Task 1.3 – Air-Set Casting Microstructure Manufacturer ASTM standard tensile bars from class 30 gray iron and Mechanical Properties and 80-55-06 ductile iron casting and collect data. Analysis (3 months) Prepare class 30 gray iron and 80-55-06 ductile iron samples for microstructural evaluation and compare to cooling curve analysis collected in Task 1.2. Task 2.1: Molding and Pouring Produce and configure thermocouples for data collection in green Operations Using Green Sand (1 sand molding. month) Pour castings 3:1 and 1:1 sand ratios for class 30 gray iron and 80- 55-06 ductile iron using baseline silica sand and ceramic media. Determine thermal diffusivity, heat capacity, temperature dependent density, and thermal conductivity values for baseline silica sand and ceramic media. Perform cooling curve analysis for baseline silica sand and ceramic media for Task 1.3. Task 2.2: Green sand castings Manufacturer ASTM standard tensile bars from class 30 gray iron

microstructure and mechanical and 80-55-06 ductile iron casting and collect data. properties (3 months) Prepare class 30 gray iron and 80-55-06 ductile iron samples for microstructural evaluation and compare to cooling curve analysis. Task 2.3 – Reporting Final report formatted for publication in AFS Transactions. PowerPoint presentation for presentation at AFS Metalcasting Congress.

3. Technical Approach and Innovation. The scope of research can be broken down in three phases, as detailed below, based upon the experimental matrix of three aggregates (two ceramic and one silica baseline sand), two molding processes, four cast alloys and two different sand: metal ratios (total of 48 unique samples). The University of Northern Iowa proposal is based and developed on utilizing the Step Block casting of section thickness of 1”, 1.5”, 2”, 2.5”, and 3” with a minimum 7” width. The width of the casting can be adjusted to obtained the desired sand to metal ratio. Experimental consideration of the proposal not only looks at the molding aggregate effect but also cooling rate aspect on the microstructural sensitivity of gray and ductile iron. Test bars can be obtained from each step section to assess cooling rate influence. However, adjustments may be made to the proposal if a smaller or standardized casting is desired to reduce the total project cost, if the committee desires, though incomplete heat saturation of the molding aggregate will significantly impact the solidification characteristics and results from using a smaller or standardized casting. The proposed research work will perform two different types of cooling analysis. First, for the mold, a reverse optimization investigation will be performed to determine the molding aggregate thermo-physical parameters using imbedded thermocouples in the mold and metal. From this approach, thermal diffusivity of the molding aggregate and associated binder is directly measured knowing the liquid-mold interface temperature and four strategically positioned thermocouples in the mold. Once thermal diffusivity is calculated, thermal property determination equipment at the UNI Metal Casting Center to measure thermal heat capacity and heat dependent density can be inserted into the thermal diffusivity equation to quantitatively calculate the temperature dependent thermal conductivity of the investigated molding aggregate. The second cooling analysis will be performed on the solidifying iron alloy and correlated to the resultant microstructure from each of the proposed section thicknesses of the Step Block casting. In this approach, the temperature-time profile is measured and the first differential is applied to this curve to create the cooling curve. Because of the unique nature and known inflection characteristics of both the temperature-time curve and cooling curve, the temperature of liquid arrest, start temperature of eutectic solidification, eutectic undercooling temperature, eutectic recalescence temperature, and end of eutectic solidification can be clearly identified. Using a neutral reference cooling curve approach, the measured thermal parameters of the mold may be used to generate a zero cooling curve and plotted with the actual iron cooling curve. Based on the area between these two curves, the percent primary austenite and percent eutectic solidification phases for each iron alloy poured can be estimated. Additionally, from the cooling curve analysis, the solidification time and solidification rate may be compared for the investigated molding aggregate and binder. Because of the strong influence of alloys on the solidification characteristics on gray and ductile iron, liquid metal chemistry needs to be strictly monitored. As an example, copper can slightly influence not only the graphitization potential of iron solidification but strongly changes the ferrite to pearlite ratio. This will have a significant influence on the microstructural analysis of both gray and ductile iron. For the proposed chemistries, alloying elements will be maintained at a target range mutually agreed upon by UNI and steering committee. It is important to maintain these alloy target ranges, especially manganese, sulfur, phosphorous, copper, tin, and, in the case of ductile iron, rare earth additions are on the low end of the target range to minimize their influence as recommended by the steering committee. UNI will incorporate strict charging order and meltdown procedures for induction melting to contribute to chemistry consistency and minimization of alloy losses. Task 1 Air-Set Analysis for Class 30 Iron and 80-55-06 Ductile Iron The objective of the first task is to explore the thermal characteristics of two iron alloys, one being class 30 cast iron and the other being 80-55-06 ductile iron, using baseline three screen, GFN 55 silica sand and two ceramic aggregates. Additionally, only the air-set phenolic urethane binder will be included. Because of the potential pouring difficulty with a previously requested 1:3 sand to metal ratio, this ratio will be excluded from Task 1. All molds will be designed using a minimum of two type S thermocouples in the metal and four type K thermocouples positioned in the mold to measure the thermal heat diffusivity for comparative heat transfer quantification. Task 1.1: Develop Patterns Four patterns will be created based on the solidification characteristics of a class 30 iron and 80-55-06 ductile poured at approximately 2500oF (1370oC). The first of two patterns will be designed for the class 30 gray iron to satisfy the sand to metal ratio of 3:1 and 1:1. The second two patterns will be designed for the 80-55-06 ductile iron alloy to achieve the desired sand to metal ratio of 3:1 and 1:1. For the class 30 iron, a 1:1:1 gating ratio will be utilized with a volume to feed riser design approach. The 80-55-06 ductile iron gating will be design with 4:8:3 ratio and the risers designed using the pressure riser method. For both iron casting designs, the gating system will be designed in order to achieve a filling velocity of 200 mm/sec or less. Upon completion of the initial gating and riser design along with the pattern layout using the high pressure green sand molding dimensions (19” x 26”), simulations using a process simulation software will be conducted to evaluate the filling dynamics and solidification characteristics, in order to assess the feeding characteristics in addition to the anticipated microstructure and mechanical properties of the cast alloys. The pattern design will be planned considering the thermo-physical properties of baseline silica sand. Additionally, the pattern will have design flexibility to be interchangeable with green sand molding as described in Task 2 and modifiable to accommodate any gray and ductile iron alloy. Prior to constructing the patterns, the pattern design will be approved by the steering committee, based on sand to metal ratios, conformity to mechanical properties testing protocols, furnace capacity, solidification modeling results and desired green sand molding properties. The selected pattern by the committee can also be used for the green sand molding process as proposed in Task 2. Upon the steering committee approval, construction of the pattern will commence using the UNI Production Lab facilities, housing a variety of wood and metal forming/removal equipment. If necessary, flask modifications will be performed if sand to metal ratios exceeds present flask dimensions within the maximum layout area of 19” x 26”. Task 1.2: Molding and Pouring Operations Using an Air-set Process All molding and pouring operation operations will be performed at the University of Northern Iowa Metal Casting Center. A phenolic urethane no-bake binder system using a 50 lb. per minute continuous mixer will be used to prepare the air set molds. A binder content of 1.25%, based on sand weight, and a Part 1 to Part 2 ratio of 55:45 will be used. Sand samples will be produced in case other thermos-physical properties are desired aside from thermal diffusivity. This would include a sample for thermal expansion testing to measure the sand density difference as a function of temperature and a bagged sample for determination of thermal heat capacity using differential thermal analysis (DSC) technique. Additionally, tensile specimen from the aggregates will be produced and measured. Loss on Ignition tests will be conducted to verify the resin content for each mold produced. Molds will be allowed to cure for a minimum 24 hours prior to pouring mold metal. For the class 30 gray iron heat, one mold of each aggregate (baseline silica, CERABEADS ceramic aggregate, and CARBO ceramic aggregate) will be produced for each sand to metal ratios proposed. A similar mold production approach will be utilized for phenolic urethane no-bake mold for 80-55-06 ductile iron alloy. During mold production, each mold will be configured with one type S thermocouple to measure the metal cooling rate and four type K thermocouples will be inserted during mold production to measure the sand thermal profile. The type K thermocouples will be located at the following distance from the anticipated mold-metal interface: 1/8”, ¼”, ½”, and 1”, respectively. Final location of the thermocouple configuration will be determined by the steering committee. From the strategic location of the thermocouples, thermal diffusivity values can be obtained. From this measurement, the thermal conductivity can be determined using a reverse optimization process based on the experimental data and analytical data. Analytical data will include: measurement of the thermal heat capacity using the DSC technique using a heating rate 20oC per minute to a final temperature 2500oF (1370oC), temperature dependent volume changes of the phenolic urethane no- bake sand sample measured by thermal dilatometry, and mass difference of the phenolic urethane no-bake sand sample measure by thermal-gravimetric analysis (TGA). As a note, only two analytical data collections per aggregate per molding process will be performed and the average of the data set will be used for processing the thermal diffusivity data for each mold poured. The ideal casting situation is to pour one aggregate for each proposed sand to metal ratio; however, the casting pouring order will need to be determined after the steering committee approves the pattern design. Additionally, proposed charge percentages might be different than commonly used in the iron industry. Higher usage of pig iron is proposed to optimize dilution of minor elements and tramp elements. For class 30 iron, a 275 lb heat will be prepared in a Pillar medium frequency induction furnace. Typical class 30 gray iron charge used at the University of Northern Iowa is 20% gray iron pig (3.6%C, 1.3%Si, 0.5%Mn, 0.05%S, and 0.05%P), 10% 1010 or low carbon steel punchings, 70% gray iron returns (3.3%C, 2.1%Si, 0.7%Mn, 0.06-0.08%S, and >0.05%P), and alloys to adjust chemistry if necessary. Melting protocols will adhere to recommended melting procedures used at the UNI Metal Casting Center. Prior to tapping, the furnace chemistry will be verified using a spectrometer and, if required, metal chemistry will be adjusted. During tapping of the furnace, a differential thermal analysis cup will be poured to measure the base metal cooling curve. After the gray iron has been inoculated with ferro-75% silicon inoculant during tapping, another differential thermal analysis cup will be poured and the cooling curve will be compared to the base metal cooling curve to assess the inoculation treatment. Concurrently, a spectrometer sample will be poured to obtain the final chemistry. The liquid metal will be transferred to the pouring area and molds will be poured starting around 2500oF (1370oC) to maximize the intended heat saturation. If successive molds are scheduled with the designated heat, the last mold will be poured at 2450oF (1343oC). The molds will be allowed to cool for at least 12 hours before extracting from the phenolic urethane molds.

For ductile iron production, similar melt preparation and protocols will be followed as previously described. For ductile iron production, the UNI Metal Casting Center will use the Foseco Flowtret process with a typical Mg recovery of 60-65%. With the assistance of the steering committee, a target Mg level will be determined for the 80-55-06 ductile iron. A typical 80- 55-06 ductile iron charge used at the University of Northern Iowa is 40% SorelTM F-1 iron pig (4.1%C, 0.2%Si, 0.15%Mn, 0.002%S, and 0.002%P), 10% 1010 or low carbon steel punchings, 50% gray iron returns (3.6%C, 2.4%Si, 0.7%Mn, >0.010%S, >0.05%P, 0.030-0.035% Mg), and alloys to adjust chemistry to meet 80-55-06 specification (to be determined by steering committee). In order to maximize the intended heat saturation, pouring will initiate at 2550oF (1400oC) and, if subsequent molds are scheduled with the designated heat, the last mold will be poured at 2500oF (1370oC). Task 1.3: Air-set Castings Microstructure and Mechanical properties Based on the presumption that a step block casting is used, the test bars will be extracted from each step, excluding the step section that contains the type-S thermocouple. The extracted metal samples will be rough lathed to obtain an approximate diameter of ¾”. Once the ¾” roughing dimension is achieved, the mechanical test specimen will be transferred to a Haas CNC lathe to be turned to a standard ASTM E8 tensile bar specimen. This tensile test bar preparation will be followed for all class 30 and 80-55-06 test castings. Tensile testing will be performed on a Satec Universal tester using a 2” extensometer. The following properties will be determined from the tensile test: yield strength, ultimate tensile strength, ductility, modulus of elasticity, reduction of area. After each sample has been mechanically tested, the fracture surface will be photographed. The fractured tensile bar will then be transferred to the Rockwell hardness tester to measure the hardness. Note: if excess metal exists from each step casting section and is of sufficient size, a Brinell hardness may be performed. Microstructure evaluation will be performed from mechanical test bar specimens. Samples will be extracted near the fracture point of the tensile test bars. Samples will be cold mounted in epoxy and polished for image analysis. Metallurgical evaluation will include: photographing the prepared microstructure as specified by AFS Procedures for graphite shape (flake and nodule), size, and distribution. Samples will then be etched using a 2% Nital solution to assess ferrite and pearlite structure. If applicable and suspected from the cooling curve analysis for each step block section, carbide identification can be performed and quantified. Task 2: Green Sand Analysis for Class 30 Iron and 80-55-06 Ductile Iron Task 2 will consist of replicating the Proposed Task 1 experiments but substituting green sand molding for air-set resin bonded molds. Pattern construction will not be required. Pattern design, as discussed in Task 1.1, will incorporate flexibility to substitute the patterns from air-set molding operations to high pressure green sand molding operations. Task 2.1: Molding and Pouring Operations Using Green Sand Pouring procedures and protocols will adhere to standards proposed in Task 1.2. For class 30 iron, a 275 lb heat will be prepared in a Pillar medium frequency induction furnace. Typical class 30 gray iron charge used at the University of Northern Iowa is 20% gray iron pig (3.6%C, 1.3%Si, 0.5%Mn, 0.05%S, and 0.05%P), 10% 1010 or low carbon steel punchings, 70% gray iron returns (3.3%C, 2.1%Si, 0.7%Mn, 0.06-0.08%S, and >0.05%P), and alloys to adjust chemistry if necessary. Melting protocols will adhere to recommended melting procedures used at the UNI Metal Casting Center. Prior to tapping, the furnace chemistry will be verified using a spectrometer and, if required, metal chemistry will be adjusted. During tapping of the furnace, a differential thermal analysis cup will be poured to measure the base metal cooling curve. After the gray iron has been inoculated with ferro-75% silicon inoculant during tapping, another differential thermal analysis cup will be poured and the cooling curve will be compared to the base metal cooling curve to assess the inoculation treatment. Concurrently, a spectrometer sample will be poured to obtain the final chemistry. The liquid metal will be transferred to the pouring area and molds will be poured starting around 2500oF (1370oC) to maximize the intended heat saturation. If successive molds are scheduled with the designated heat, the last mold will be poured at 2450oF (1343oC). The molds will be allowed to cool for at least 12 hours before extracting from the phenolic urethane molds. For a typical 80-55-06 ductile iron charge used at the University of Northern Iowa is 40% SorelTM F-1 iron pig (4.1%C, 0.2%Si, 0.15%Mn, 0.002%S, and 0.002%P), 10% 1010 or low carbon steel punchings, 50% gray iron returns (3.6%C, 2.4%Si, 0.7%Mn, >0.010%S, >0.05%P, 0.030-0.035% Mg), and alloys to adjust chemistry to meet 80-55-06 specification (to be determined by steering committee). In order to maximize the intended heat saturation, pouring will initiate at 2550oF (1400oC) and, if subsequent molds are scheduled with the designated heat, the last mold will be poured at 2500oF (1370oC). For green sand molding on the UNI high pressure green sand molding equipment will be performed on the day of a scheduled heat. Prepared and pre-conditioned green sand (baseline GFN 55 silica sand and two ceramic aggregates) will be prepared in 1200 lb. batches using a vertical wheel muller using 100% sodium bentonite, with a target active clay level of 8% and 1.6% seacoal, based on batch weight, as per standard cast iron green sand practices. Prior to transferring the green sand mixture to the high pressure green sand molding equipment, the compatibility (AFS 2220-00-S) will be recorded. The green sand will not be discharge from the muller unless the compatibility is within the range of 39-43. Green sand samples will be retained in a sealed bag for the following tests: green compression (AFS 5202-00-S), moisture content (AFS 2116-00-

S), LOI (AFS 5100-00-S), methylene blue for active clay (AFS 2210-00-S), and 25 micron clay wash for total clay (AFS 2111- 00-S). Additions of clay and seacoal will be performed accordingly for subsequent usage based on previous pouring operations. Prior to closing the together, the mold hardness will be recorded (AFS 2230-00-S) for both sides of the molds. Depending on the number of molds scheduled, green sand molds will be poured within 90 minutes of producing the first mold. During the production of the green sand molds, each mold will be configured with one type S thermocouple to measure the metal cooling rate and 4 type K thermocouples will be inserted during mold production to measure the sand thermal profile. The type K thermocouples will be located at the following distance from the anticipated mold-metal interface: 1/8”, ¼”, ½”, and 1”, respectively. Location of the thermocouples will be determined as discussed in Task 1.2. Task 2.2: Green sand castings microstructure and mechanical properties The test bars obtained from both ceramics using a green sand molding process will be evaluated for their microstructure and mechanical properties. Mechanical properties will include: yield strength, tensile strength, modulus of elasticity, ductility, reduction of area, and hardness (Rockwell and/or Brinell). For mechanical testing, test bar standard will be selected under advisement of the research project steering, depending on the casting design. Samples will be extracted from the casting as specified by the steering committee. Extracted will be manually roughed to a standard cylindrical diameter as specified by the ASTM E8 standard. The shoulder and mechanical test area of the tensile test bar will be CNC lathed to maintain dimensional tolerances. After mechanical testing, the mechanical test area will be Rockwell hardness tested. Fracture surface will be photograph with a macroscopic. An area near the fracture surface will be extracted for metallurgical evaluation and preparation will followed method proposed in Task 1.3. Task 2.3: Reporting Two forms of reporting will be used for the proposed research program. Quarterly status reports will be submitted to the steering committee by the research team to keep the associated committee informed on the direction and status of the work. The second form of reporting will be aimed towards disseminating the research information to the foundry industry. This will be include a final detailed report, including results, methodologies and analysis, technical papers at the AFS Casting Congress and presentations for AFS casting shows and chapter meetings. 4. Project Technical Team Dr. Scott Giese, University of Northern Iowa Foundry Education Foundation (FEF) Key Professor, has been a faculty member in the Department of Technology since 2003. Dr. Giese has two technical degrees from Erie Community College in engineering science and materials science and B.S., M.S., and Ph.D. degrees in Metallurgical Engineering from the University of Alabama in Tuscaloosa. After completing his doctoral requirements in 1995, he was employed at the University of Northern Iowa Metal Casting Center as a research project manager, working with the foundry industry and government agencies in applied research projects related to foundry technologies. He has authored or co-authored 33 papers and conducted over 60 technical presentations on a variety of topics related to foundry processes. His research interests include: mold and making processes, sand additives, solidification science, , and foundry process control. Dr. Giese is an active member of the American Foundry Society and presently serves on the AFS 4A, 4B, 4C, and 4F Committees. In the fall of 2012, he was awarded the FEF/AFS Distinguished Professor Award at the FEF College Industry Conference. At the 2013 Cast Expo, Dr. Giese received the AFS Scientific Merit Award and the AFS Copper Alloy Division Service Award. In 2014 and 2019, he was awarded the Molding Methods and Materials Division Best Paper Award and Best Presentation Award. Dr. Giese presently working on Defense Logistics Agency exploring the formation of highly oxidative casting alloys during casting filling. 5. Timeline; Table 1 shows the breakdown of costs and proposed timeline. Table 1: Breakdown of costs and projected timeline Task Phase Description Cost ($) Timeline (months) 1 Air-Set Analysis for Class 30 Iron & 80-55-06 Ductile Iron $62,025.00 7 months 2 Green Sand Analysis for Class 30 & 80-55-06 Ductile Iron $60,050.00 5 months Total $122,075.00 12 months

6. Budget & Industry In-Kind support;

Task Description AFS Funds In-kind Total Task 1 Air-Set Analysis for Class 30 Iron and 80-55-06 Ductile Iron $38,134 $23,891 $62,025 Task 1.1: Develop Patterns $8,800 $4,400 $13,200 Task 1.2: Molding and Pouring Operations Using an Air-Set Process $19,734 $14,691 $34,425 Task 1.3: Air-Set Castings Microstructure and Mechanical properties $9,600 $4,800 $14,400 Task 2: Green Sand Analysis for Class 30 Iron and 80-55-06 Ductile Iron $32,666 $27,384 $60,050 Task 2.1: Molding and Pouring Operations Using Green Sand $19,733 $14,917 $34,650 Task 2.2: Green Sand Castings Microstructure and Mechanical $9,600 $4,800 $14,400 Properties Task 2.3: Reporting $3,333 $7,667 $11,000 Total Funds $70,800 $51,275 $122,075 In-kind support includes tentative $35,400 contribution from Ductile Iron Society based upon approval by the American Foundry Society. Anticipated materials donations is $9,875. Dr. Scott R Giese will cost share 5% of his academic time for supervising, training 2-3 undergraduate students and reporting at an estimated value $6,000 and the total amount has been added in Task 2.3 in-kind column. 7. Justification and Economic Significance to Industry Because of the recent enactment and enforcement of OSHA Silica Rule, foundries have quickly addressed fugitive silica issues to mediate certain areas in the foundry to comply with the rule. Some foundries have decided to switch to non-crystalline molding aggregates without consideration to the thermal impact of their present casting designs. Within the cast iron industry, small deviations in cooling rates can rapidly change casting quality by moving the desired shrinkage area located in the riser to areas within the casting or changing the mechanical properties through deviations in the ferrite to pearlite ratio or increased carbides. The proposed research work addresses a significant concern in changing molding media using a microstructural sensitive alloy such as gray and ductile iron. Knowledge in these solidification characteristics from different molding media can save the foundry industry millions of dollars resulting from potentially increased shrinkage defects, out-of-specification mechanical properties, and/or expensive tooling design changes to accommodate the thermal property differences between ceramic aggregate and silica sand. The objective of the research program is to develop a thermal and physical properties database that can be used in solidification modeling programs to assess solidification changes prior to adopting alternative molding aggregates. A cost analysis by the foundry can then be performed to compare potential design changes to other remediation actions addressing compliance to the OSHA Silica Rule. 8. Technology Deployment Plan The information gather from the proposed research work will be distributed to the foundry through publication and presentations at AFS events. Additionally, temperature dependent thermal property data will be available for individual and corporate members to be included in commercial solidification modeling software programs. The proposed research program is designed to demonstrate reactionary changes to the molding process addressing the OSHA Silica Rule can result in solidification behavioral changes resulting in shrinkage migration from the riser to the casting or microstructural alterations creating mechanical properties differences leading to quality issues. By investigating gray and ductile iron, subtle changes in thermal properties can be clearly demonstrated to the foundry industry that process changes might require casting design evaluation prior to silica abatement decisions through the use of alternative molding aggregates. 9. Research Agency and PI qualifications The University of Northern Iowa Metal Casting Center (MCC) is located at the Department of Industrial Technology in Cedar Falls, IA. The MCC research facilities include all equipment needed to perform a wide range of processes and production techniques commonly utilized in the foundry industry. Additionally, the University of Northern Iowa Manufacturing Engineering Technology – Metal Casting has four courses directly associated with the foundry industry. The first full semester course is TECH 3127 Transport Phenomena teaching students primarily on classic thermodynamics, fluid dynamics, and heat transfer with a strong integration Flow 3D simulation software. TECH 3134 Molding Practices explores green sand molding preparation and process control procedures, all chemical bonded molding processes, permanent mold, , and . TECH 4136 Melting and Metallurgy Practices covers furnaces, refractories, slag/dross formation, and melt quality practices for ferrous and nonferrous metals including cooling curve analysis of gray iron inoculation and ductile iron production. Finally, TECH 4137 Tooling Practices covers gating and riser design for ferrous and nonferrous casting alloys utilizing Magma v5.3 casting simulation software for design verification. The principal investigator for the proposed research work is Dr. Scott R. Giese, Foundry Education Foundation Key professor at the University of Northern Iowa. Dr. Giese will serve as the project manager and technical researcher for proposed tasks. He has been with the University of Northern Iowa for 21 years, serving as a research project manager for the Metal Casting from 1995 to 2003 and transferred to the faculty staff in 2003 and has received the rank of professor in 2013. His casting expertise is metal casting processes with a strong emphasis in melting practices, sand molding defect analysis, and thermal analysis related to melting operations and resin binder decomposition associated with VOC and HAP emissions. Casting design and solidification modeling is another research interest of Dr. Giese and provides assistance to the UNI Metal Casting Center in this area, in addition to teaching two undergraduate and one graduate level course every semester. Sariam Ravi, research project manager for the University of Northern Iowa Metal Casting Center, will serve as project coordinator and technical research for proposed activities performed at the University of Northern Iowa. He has been with the Metal Casting Center as a research project manager since 2011. Sairam oversees and coordinates all applied research and business assistance activities for the Metal Casting Center. As the Metal Casting Center project manager, he knows how to operate all the foundry and analytical equipment and supervises the students in conducting research. His research interests include thermo-physical properties analysis for metals and sands, casting design, molding process improvements and testing, and additive manufacturing for metal casting. Additionally, he has been developing Application Programming Interface (API) codes for a CFD software vendor to model thermo-mechanical stress during sand expansion to cause veining defects and gas evolution. A wide variety of foundry processes are available at the UNI MCC and has personnel, equipment and expertise to work numerous components as proposed in the proposal. The organizational structure of the Metal Casting Center is an executive director, two project managers with one managing the Metal Casting Center operations and the other managing the Additive Manufacturing Center operations, and three research associates. The UNI MCC employs over 20 UNI students to provide technical learning opportunities and experience. Two to four undergraduate students will be employed specifically for the proposed research work to assist in the analytical experiments, preparing molds and iron heats, and perform experimental data collection. Molding processes available at the UNI MCC facilities include green sand (high pressure molding and jolt squeeze methods), phenolic urethane, phenolic ester, sodium silicate, shell, investment and die casting. Core-making processes include cold and hotbox core blowing technologies. Melting capacity includes capability for 300 lbs. of ferrous or copper alloys and 75 lbs. of aluminum alloys. Specifically for iron casting operation proposed, a eutectometer and cooling curve analysis will be used as preliminary chemistry check and as inoculation effectiveness assessment. Final chemistry is verified with a Spectro spectrometer. A wide range of standard laboratory equipment for mechanical and physical testing, thermo-physical properties and precise chemistry characterization is available at the MCC. Equipment includes a differential scanning calorimeter (DSC) coupled with thermo-gravimetric analysis (TGA) and mass spectrometer (MS), dilatometer, thermal analysis unit, X-Ray Fluorescence (XRF) spectrometer, ultrasonic testing equipment and complete sand-testing laboratory for green sand and chemical bonded processes. Mechanical metallurgy is accomplished using a Satec universal tester with a 60,000 lb load cell, a Satec impact tester for Izod and Charpy samples, Rockwell hardness tester for a variety of scale ranges including B- and C-scale, a Brinell hardness tester, and/or Knoop/Vickers hardness tester. Qualitative and quantitative microsctructural analysis will be performed in the department metallurgy lab. Metallurgical samples are sectioned and prepared using either hot or cold mounting methods. Two Leco polishing and one Leco grinder are available to prepare metallurgical samples for rough preparation. Two Leco polishing equipment are dedicated for fine grinding and polishing purposes. The lab has appropriate chemical hoods and sample preparation area for chemical etching. Prepared samples are analyzed using Pax-It 2 image analysis software connected to a Leco microscope with magnification range of 100 to 1000X. The department Production Lab is a 50,000 square foot facility, primarily used for woodworking and metal working. In support of the proposed project, the woodworking area has a comprehensive collection of equipment necessary for manual pattern making. The metal working area has numerous manual mills and lathes, and CNC mills and lathes for test bar production. Additionally, the Metal Casting Center has a discount pricing arrangement with the UNI Additive Manufacturing Center for producing tooling and/or cores if required. The Metal Casting Center and department complies with all federal and state regulations for safety and waste material disposal. All personnel associated with the Metal Casting Center (staff, faculty, and students) receive OSHA (students taking TECH 3196 Industrial Safety can complete and receive their 30 hour OSHA card) periodic training; facilities comply to NIOSH standards related to liquid metal handling; performs bi-annual chemical handling and disposal training through the university; and meets all waste disposal guidelines mandated by the State of Iowa. Selected Relevant Peer Reviewed Papers 1. “Case Study: Reducing Shrinkage in Aluminum Castings using Thermal Management of PUCB Resin System”, Beirsner, B., Ravi, S., and Giese, S.R., AFS Transactions, Volume 126, Paper 18-100 2. “Division 4 Silver Anniversary Paper - Review of Cast Iron Metal Penetration”, S.R. Giese, AFS

Transactions, Volume 125, Paper 17-126 3. “Use of Sintered Bauxite in Molding Applications”, S.R. Giese, AFS Transactions, Volume 123, 2015, Paper 15-075. 4. “Preliminary Investigation on the Effect of Binder Content and Ratio on Heat Transfer”, S.R. Giese, S. Ravi, K. Boss, and B. Biersner, AFS Transactions, Volume 120, 2012, Paper 09-112. 5. “Thermal Analysis of Phenolic Urethane”, S.R. Giese, Sean Roorda, and Mitch Patterson, AFS Transactions, Volume 117, 2009, Paper 09-112. 6. “Numeric Ranking of Step Cone Test Castings”, S.R. Giese and G. Thiel, AFS Transactions, Volume 115, 2007, Paper 07-102. 7. "Use of a Synthetic Ceramic Material in Molding Applications", S.R. Giese and Claude Krause, AFS Transactions, vol. 108, 2000. 10. Reporting Two forms of reporting will be used for the proposed research program. The first form of reporting is to meet the requirements of the funding agency, namely, AFS. For the project management component, quarterly status reports will be submitted to the steering committee by the research team to keep the associated committee informed on the direction and status of the work. Upon approval of the progress of the quarterly report, the steering committee will submit this report to the AFS Research Board. As part of the project management update requirement, a one-page executive report will be submitted to the AFS Vice President of Technical highlighting the research accomplishments, planned research activities for the for following quarter, and, if necessary, identification of programmatic issues that might result in delays or changes in project activities. The second form of reporting will be aimed towards disseminating the research information to the foundry industry. This will be include a final detailed report, including results, methodologies, analysis, and conclusions using the AFS Casting Congress standard paper format. AS part of the paper submission for publishing in the AFS Conference Proceeding, a presentation will be requested for the conference as sole presenter made either by the principal investigator or as a Cast Iron Division panel discussion. Upon completion of the project, it is anticipated further dissemination of the information will be made at AFS Regional Conferences, AFS local chapter meetings, and other foundry conference avenues. 11. Intellectual Property No intellectual property generation anticipated during the proposed research work. 12. Collaboration Thermal property data generated from the proposed research work is anticipated to be distributed to the casting simulation vendors associated with AFS. The materials property dataset will be recommended to be included into their general database. Additionally, AFS members can be furnished the data upon request and anticipated to be distributed through AFS.

Steering Committee Chair: Brandon Reneau (Caterpillar) Steering Committee Members: Matt Meyer (Kohler), Liz Medina (Neenah Foundry)

SUBMISSION Submit Research proposals to: AFS Chief Technical Services Officer American Foundry Society 1695 North Penny Lane Schaumburg IL 60173 Phone: 847/824-0181

AFS R&D Project Committee Tracking & Division Approval Form

Project Title: Effect of Ceramic Sand on Cast Iron Mechanical Properties

Principal Investigator: Dr. Scott R. Giese Affiliation: University of Northern Iowa

AFS Division Request No.: Cast Iron Request Date: August 7, 2019 AFS Committee: Cast Iron research

NAME ACTION INITIATOR DATE SIGNATURE (or email notice) ASSIGN AD HOC REVIEW COMMITTEE AFS COMMITTEE CHAIR

COMMITTEE DISPOSITION AD HOC CHAIR (attach minutes)

If approved, a monitoring steering committee must be identified below. Division approval is indicated by endorsement in the signature block below. If not approved, notify the Division Chair (copy AFS staff liaison & VP Tech serv.) for communication of this decision to the applicant.

DIVISION APPROVAL/REJECTION DIVISION CHAIR

DISTRIBUTE PROPOSAL TO RESEARCH BOARD & AFS V.P. TECHNICAL SERVICE ASSIGN MEETING DATE

ADVISE PRESENTER OF RESEARCH BOARD REVIEW AFS V.P. TECHNICAL SERVICES DATE

Steering Committee Assignment (Minimum of Two)

CHAIR Name Signature

Affiliation Date

Tel Email

MEMBER Name Signature

Affiliation Date

Tel Email

MEMBER Name Signature

Affiliation Date

Tel Email

MEMBER Name Signature

Affiliation Date

Tel Email

MEMBER Name Signature

Affiliation Date

Tel Email DIVISION Name Signature APPROVAL Affiliation Date

Tel Email