DESIGN GUIDE

AlBeCast® COMPOSITE DESIGN GUIDE

A guide to designing a more economical and producible investment casting. www.materion.com/AlBeCast

What design challenges are you facing today? Materion's AlBeCast® product line is a family of investment cast aluminum-beryllium metal matrix composites that provides designers a net-shape product. This publication is intended to provide a general overview of the aluminum beryllium investment casting process and to assist engineers in designing a more economical and producible investment casting. These are general guidelines and recommendations. They do not represent all of the detail limitations of the process. This document is intended to help engineers understand the aluminum beryllium casting process capabilities, process limitations and typical properties. If there is a particular design issue not covered in this guide, please contact Materion.

EXECUTIVE SUMMARY Property AlBeCast 910® Composite AlBeCast 920® Composite Nominal Beryllium Wt 60% 65% Additional Elements Al, Ni Al, Ag, Co, Ge 2.17 g/cm3 2.17 g/cm3 Density [0.078 lbs/in3] [0.078 lbs/in3] 14.6 ppm/C° 14.2 ppm/C° Coefficient of Thermal Expansion [8.1 ppm/F°] [7.9 ppm/F°] 193 GPa 202 GPa Modulus of Elasticity in Tension [28.0 Mpsi] [29.3 Mpsi] 147.5 MPa 213.7 MPa Yield Strength (0.2 % Offset) [21.4 Ksi] [31.0 Ksi] 196.5 MPa 289.6 MPa Ultimate Tensile Strength [28.5 Ksi] [42.0 Ksi] Elongation (1" Gage) 4.7% 3.0%

KEY REQUIREMENTS: • Identify critical sections and surfaces • The ideal wall thickness is between 0.08" and 0.12" • Utilize locator pads to define datums [2 mm to 3 mm] • Build datums as close to the center-line • The minimum wall thickness is 0.06", the maximum of the component as possible typical wall thickness is 1". [Minimum of 1.5 mm, maximum typical of 25 mm] • Dimensional tolerance is based on size • Minimize the use of small, deep pockets - ± 0.030" up to 8", ± .060" for the largest parts or blind holes - ± 0.75 mm up to 200 mm, ± 1.5 mm for the largest parts • Avoid sharp corners and transitions, use generous fillets and radii when possible • The maximum AlBeCast composite component weight is 30 lbs [13.6 kg] • Keep wall thickness constant • The maximum AlBeCast composite • Various AlBeCast material specifications exist for component size is 20" x 20" or 24" diameter aerospace, commercial and prototype components [500 mm x 500 mm or 600 mm diameter] PROCESS Materion's AlBeCast® product is a two phase material Melting and casting are done under vacuum. consisting primarily of beryllium intermixed with Materion’s aluminum beryllium investment casting aluminum. Beryllium provides the alloy with strength process, including wax injection, shell making, degating, and stiffness and aluminum provides ductility. These straightening and nondestructive testing (NDT) is materials are metal matrix composites in that the very similar to the aluminum investment casting process. microstructure is mixture of a brittle, high strength Materion’s aluminum beryllium investment casting phase, (Be) and a ductile lower strength phase (Al). process is capable of using either conventional wax The difficulties in casting AlBeCast material is due to patterns or rapid prototype technology. AlBeCast the lack of solubility between beryllium and aluminum, materials are produced by vacuum casting molten and the fact that beryllium is a very reactive metal. metal into hollow “ceramic shells” which reproduce When operating at the high casting temperatures the desired component dimensions. The ceramic shells required, molten beryllium will react with most are manufactured from a unique, non-reactive ceramic refractories commonly used for crucibles and invest- formulation. Casting and solidification is conducted ment molds. Crucible reactions produce inclusions, under controlled conditions to produce the highest while mold reactions cause porosity and poor surface quality casting. Post-cast processing, including deshell- quality. Additionally, AlBeCast materials have a solidifi- ing, gate removal, straightening, finishing and inspection cation range of 605 C° [1121 F°]. Materials with such follow aluminum industry practice. The AlBeCast a wide solidification range present unique challenges. product line can be repaired, straightened and AlBeCast composites are produced in a dedicated welded enabling a reduction in costs. aluminum beryllium investment casting facility.

PROTOTYPING Aluminum beryllium castings can be successfully cast using rapid prototype processes. Rapid prototyping processes have advantages and disadvantages over hard tool methods.

PROTOTYPE ADVANTAGES: PROTOTYPE DISADVANTAGES: • Quick - takes typically 6-8 weeks from • Individual rapid prototype patterns are expensive electronic file to cast part • Yields a rougher surface finish than a hard • Allows multiple design iterations prior to tooled casting committing to long lead hard tooling • Thin sections can be difficult to produce using • Geometrically flexible SLA technology • Cost effective for limited runs ADVANTAGES OVER A356 ALUMINUM • ~22% lower density • ~40% lower in coefficient of thermal • ~3 times stiffer (modulus of elasticity in tension) expansion (CTE) • Up to 10 times better in damping coefficient • ~50% higher specific heat • ~28% higher thermal conductivity

ADVANTAGES OVER BERYLLIUM • ~3 times greater ductility than hot pressed • Reduced environmental processing beryllium with greater damage tolerance concerns resulting from reduced waste • Castable for complex and precise • Does not require chemical etching net shape configurations • Reduced material usage • Weldable for defect repair • Reduced cost • Reduced machining and scrap generation

PROPERTIES Property AlBeCast® 910 Composite AlBeCast® 920 Composite Nominal Beryllium Wt % 60 65 Additional Elements Al, Ni Al, Ag, Co, Ge 2.17 g/cm3 2.17 g/cm3 Density [0.078 lbs/in3] [0.078 lbs/in3] 14.6 ppm/C° 14.2 ppm/C° Coefficient of Thermal Expansion [8.1 ppm/F°] [7.9 ppm/F°] 193 GPa 202 GPa Modulus of Elasticity in Tension [28.0 Mpsi] [29.3 Mpsi] 147.5 MPa 213.7 MPa Yield Strength (0.2 % Offset) [21.4 Ksi] [31.0 Ksi] 196.5 MPa 289.6 MPa Ultimate Tensile Strength [28.5 Ksi] [42.0 Ksi] Elongation (1" Gage) 4.7% 3.0% 1560 J/Kg C° 1250 J/Kg C° Specific Heat [0.36 Btu/lb F°] [0.30 Btu/lb F°] 110.0 W/m K° 105.5 W/m K° Thermal Conductivity [64.0 Btu/hr ft F°] [61.0 Btu/hr ft F°] 88.9 GPa cm3/g 93.1 GPa cm3/g Specific Stiffness [358.9 Mpsi in3/lb] [375.6 Mpsi in3/lb] Poissons Ratio 0.154 0.20 90.6 MPa cm3/g 133.5 MPa cm3/g Specific Strength [365.4 Ksi in3/lb] [538.5 Ksi in3/lb] 86.2 MPa 117.2 MPa Axial Fatigue (R=-1, K =1, 10^7 Cycles) t [12.5 Ksi] [17.0 Ksi] 147.0 MPa 226.1 MPa Compressive Yield [21.3 Ksi] [32.8 Ksi] 181.0 MPa 247.5 MPa Pin Double Shear Strength [26.3 Ksi] [35.9 Ksi] Electrical Conductivity 48% IACS 40% IACS AlBeCAST® 910 COMPOSITE TENSILE PROPERTIES VS TEMP AlBeCAST® 910 COMPOSITE COMPRESSIVE STRENGTH VS TEMP 35 7 25 AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE TENSILE TENSILE PROPERTIES PROPERTIES VS TEMP VS TEMP AlBeCASTAlB®e 910CAST COMPOSITE® 910 COMPOSITE COMPRESSIVE COMPRESSIVE STRENGTH STRENGTH VS TEMP VS TEMP AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE TENSILE TENSILE PROPERTIES PROPERTIES VS TEMP VS TEMP AlBeCASTAlB®e 910CAST COMPOSITE® 910 COMPOSITE COMPRESSIVE COMPRESSIVE STRENGTH STRENGTH VS TEMP VS TEMP 35 35 30 7 7 25 25 6 35 35 7 7 25 25 20 30 30 25 6 6 5 30 30 6 6 20 20 15 25 25 20 5 5 20 20 4 25 25 5 5 15 15 20 20 15 4 4 3 15 15 10 20 20 4 4 Elongation % Strength (Ksi) 10 2 15 15 3 3 10 10 15 15 3 3 10 10 5 Elongation % Elongation % Strength (Ksi) 10 Strength (Ksi) 10 5 2 2 1 Elongation % Elongation % Strength (Ksi) 10 Strength (Ksi) 10 2 2

5 5 Compressive Yield Strength (Ksi) 5 5 0 1 1 5 5 0 0 5 5 -100 0 1 1001 200 300 400 500 0 500 1000 1500 2000 Compressive Yield Strength (Ksi) Compressive Yield Strength (Ksi)

0 0 0 0 Compressive Yield Strength (Ksi) 0 Compressive Yield Strength (Ksi) 0 0 -100 0 -1000 0100 100200 200300 300400 400500 0500 0 Temperature (F)0 0 0 0 500 500 1000 1000 1500 1500 2000 2000 Temperature (F) -100 -1000 0100 100200 200300 300400 400500 500 0 0 500 500 1000 1000 1500 1500 2000 2000 TemperatureTemperature (F) (F) UTS YS ELONG TemperatureTemperature (F) (F) TemperatureTemperature (F) (F) TemperatureTemperature (F) (F) UTS UTSYS YSELONGELONG UTS UTS YS YSELONGELONG

AlBeCAST® 910 COMPOSITE CTE VS TEMP AlBeCAST® 910 COMPOSITE AXIAL FATIGUE (R=-1) 10 14 AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE CTE VS CTE TEMP VS TEMP AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE AXIAL AXIALFATIGUE FATIGUE (R=-1) (R=-1) AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE CTE VS CTE TEMP VS TEMP AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE AXIAL AXIALFATIGUE FATIGUE (R=-1) (R=-1) 10 10 9 14 14 20 10 10 14 14

9 9 8 20 20 16 9 9 20 20

8 8 7 16 16 12 8 8 16 16

7 7 6 12 12 Stress (Ksi) 8 7 7 CTE (ppm/°F) 12 12

6 6 Stress (Ksi) 8 Stress (Ksi) 8

CTE (ppm/°F) CTE (ppm/°F) 5 4 6 6 Stress (Ksi) 8 Stress (Ksi) 8 CTE (ppm/°F) CTE (ppm/°F) 5 5 4 4 4 0 5 5 -300 -200 -100 0 100 4 200 4 300 400 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 4 4 0 0 4-300 4-300-200 -200-100 -1000 0100 100200 200300 300400 400 Temperature (F)1.E+040 1.E+040 1.E+05 1.E+051.E+06 1.E+061.E+07 1.E+071.E+08 1.E+081.E+09 1.E+09 Cycles to Failure -300 -300-200 -200-100 -1000 0100 100200 200300 300400 400 1.E+04 1.E+041.E+05 1.E+051.E+06 1.E+061.E+07 1.E+071.E+08 1.E+081.E+09 1.E+09 TemperatureTemperature (F) (F) Cycles Cyclesto Failure to Failure TemperatureTemperature (F) (F) Cycles Cyclesto Failure to Failure

AlBeCAST® 910 COMPOSITE POISSON’S RATIO VS TEMP AlBeCAST® COMPOSITE DIMENSIONAL TOLERANCE 0.16 0.08 AlBeCASTAlB®e CAST910 COMPOSITE® 910 COMPOSITE POISSON’S POISSON’S RATIO VSRATIO TEMP VS TEMP AlBeCASTAlB®e CASTCOMPOSITE® COMPOSITE DIMENSIONAL DIMENSIONAL TOLERANCE TOLERANCE ® ® ® ® AlBeCASTAlBe CAST910 COMPOSITE 910 COMPOSITE POISSON’S POISSON’S RATIO VSRATIO TEMP VS TEMP AlBeCASTAlBe CASTCOMPOSITE COMPOSITE DIMENSIONAL DIMENSIONAL TOLERANCE0.07 TOLERANCE 0.16 0.16 0.15 0.08 0.08 0.16 0.16 0.08 0.08 0.07 0.07 0.06 Recommended 0.15 0.15 0.14 0.07 0.07 0.15 0.15 0.06 0.06 RecommendedRecommended 0.05 0.06 0.06 RecommendedRecommended 0.14 0.14 0.13 0.04 0.14 0.14 0.05 0.05 Consult Materion 0.05 0.05 0.03 0.13 0.13 0.12 0.04 0.04 Consult MaterionConsult Materion

0.13 0.13 Poisson’s Ratio 0.04 0.04 Consult MaterionConsult Materion 0.03 0.03 0.02 0.12 0.12 0.11 0.03 0.03 Requires Machining Poisson’s Ratio 0.12 Poisson’s Ratio 0.12 0.02 0.02 0.01 Poisson’s Ratio Poisson’s Ratio

0.02 0.02 Dimensional Tolerance (Inches) 0.11 0.11 0.1 RequiresRequires Machining Machining0 0.11 0.11 0.01 0.01 RequiresRequires Machining Machining 0 50 100 150 200 2500.01 3000.01 350 400 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 Dimensional Tolerance (Inches) Dimensional Tolerance (Inches)

0.1 0.1 Dimensional Tolerance (Inches) 0 Dimensional Tolerance (Inches) 0 0.1 0 0.1 500 10050 100150 150200 200250 250300 300350 350400 400 Temperature (F) 0 0 20 04 26 48 610 812 1014 1216 1418 1620 1822 2024 2226 2428Component2630 28 30 Maximum Dimension (Inches) 0 500 10050 100150 150200 200250 250300 300350 350400 400 0 2 04 26 48 610 812 1014 1216 1418 1620 1822 2024 2226 2428 2630 28 30 TemperatureTemperature (F) (F) ComponentComponent Maximum Maximum Dimension Dimension (Inches) (Inches) TemperatureTemperature (F) (F) ComponentComponent Maximum Maximum Dimension Dimension (Inches) (Inches)

AlBeCAST® COMPOSITE WALL THICKNESS 0.60 AlBeCASTAlB®e CAST COMPOSITE® COMPOSITE WALL THICKNESS WALL THICKNESS AlBeCASTAlB®e CAST COMPOSITE® COMPOSITE WALL THICKNESS WALL THICKNESS Consult Materion 0.60 0.60 0.50 0.60 0.60 Consult MaterionConsult Materion Consult MaterionConsult Materion 0.50 0.50 0.40 0.50 0.50 Recommended Range

0.40 0.40 0.30 0.40 0.40RecommendedRecommended Range Range RecommendedRecommended Range Range 0.30 0.30 0.20 0.30 0.30 Ideal Range 0.20 0.20 Consult Materion

Wall Thickness (Inches) 0.10 0.20 0.20 Ideal RangeIdeal Range Ideal RangeIdeal Range Not Recommended Consult MaterionConsult Materion Wall Thickness (Inches) 0.10 Wall Thickness (Inches) 0.10 0.00 Consult MaterionConsult Materion

Wall Thickness (Inches) 0.10 Wall Thickness (Inches) 0.10 Not RecommendedNot Recommended0 2 4 6 8 10 12 14 16 18 20 0.00 0.00 Not RecommendedNot Recommended 0.00 0 0.0020 42 64 86 108 1210 1412 1614 1816Component2018 20 Maximum Dimension (Inches) 0 20 42 64 86 108 1210 1412 1614 1816 2018 20 ComponentComponent Maximum Maximum Dimension Dimension (Inches) (Inches) ComponentComponent Maximum Maximum Dimension Dimension (Inches) (Inches) DIMENSIONAL RECOMMENDATIONS These dimensional recommendations are applicable Identification and design of critical features and to all AlBeCast® materials although the AlBeCast 910 surfaces is vital for cost-effective production of product line can be less difficult to cast therefore aluminum beryllium cast components. The cost allowing some variation in design. of a casting increases in relation to the complexity Aluminum beryllium castings have dimensional of the design and the level of precision required. stability on par with standard aluminum investment Contact Materion to review critical component castings. As the size of the feature increases, so will features early in the design process. the dimensional variation. If features require tighter tolerances, they can be machined into the product if sufficient clean stock is available.

FACTORS INFLUENCING LINEAR TOLERANCES • Component size • Wax processing and assembly • Metal pouring conditions • Component geometry • Casting feed design • Mold removal procedures • Wall thickness • Shell processing and • Post casting processing • Wax injection tool shell type

DATUM SETUP Aluminum beryllium castings are dimensioned from Location points can be cast into the surface of the “datum” planes. Proper selection and orientations part to define the points on which the datums are of the casting datum planes is critical to cost-effective located. These points may be any size, but are often casting inspection and machining. designed as a cylindrical boss, 0.3" in diameter, 0.06" A datum is simply a plane defining the zero from tall. These location points should also serve as clamp which all dimensions are measured. For casting points for any machining operation which is why often design, it is typical to choose three datum planes times the location points are established on tooling at right angles to each other. In this way all dimen- lug features. sions in all three orthogonal directions can be Most cylindrical parts do not fall neatly into the uniquely defined without ambiguity. classical six-point location system. The best method Six points are required to define the position of of defining a cylindrical part utilizes a three-jaw chuck a component with orthogonal datum planes. The to center the major diameter of the part. This chuck 3,2,1 arrangement uses three points to define datum is the equivalent of a two points, since it defines an A, two points to define datum B and one point axis. Three points longitudinally abutting the jaws to define datum C. The points defining each datum define a plane at a right angle to the central axis. should be spaced as widely as possible to maximize A final “clocking” point completes this datum scheme. accuracy. However, in order to reduce the errors, the datum planes themselves should be as close to the center of the part as possible. AlBeCAST® 910 COMPOSITE TENSILE PROPERTIES VS TEMP AlBeCAST® 910 COMPOSITE COMPRESSIVE STRENGTH VS TEMP 35 7 25

30 6 20 25 5 15 20 4

15 3 10 Elongation % Strength (Ksi) 10 2 5 5 1 Compressive Yield Strength (Ksi) 0 0 0 -100 0 100 200 300 400 500 0 500 1000 1500 2000

Temperature (F) Temperature (F)

UTS YS ELONG

AlBeCAST® 910 COMPOSITE CTE VS TEMP AlBeCAST® 910 COMPOSITE AXIAL FATIGUE (R=-1) 10 14

9 20

8 16

7 12

6 Stress (Ksi) 8 CTE (ppm/°F)

5 4

4 0 -300 -200 -100 0 100 200 300 400 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09

Temperature (F) Cycles to Failure LINEAR TOLERANCE Dimensional tolerance should be based on the maximum size of the component. The listed values are typical. Tighter tolerances have been achieved, please consult Materion if tighter tolerances are necessary. These tolerances are applied to the entire surface of a component, as defined by a CAD model.

AlBeCAST® 910 COMPOSITE POISSON’S RATIO VS TEMP AlBeCAST® COMPOSITE DIMENSIONAL TOLERANCE DIMENSIONS TYPICAL DIMENSIONS TYPICAL 0.16 0.08 Up to 1" ± 0.010" Up to 25 mm ± 0.25 mm 0.07 0.15 Up to 4" ± 0.020" Up to 100 mm ± 0.50 mm 0.06 Recommended 0.14 Up to 8" ± 0.030" Up to 200 mm ± 0.75 mm 0.05

0.13 Up to 12" ± 0.040" Up to 300 mm ± 1.00 mm 0.04 Consult Materion 0.03 0.12 Up to 20" ± 0.050" Up to 500 mm ± 1.25 mm Poisson’s Ratio 0.02 Up to 30" ±0.060" Up to 750 mm ± 1.50 mm 0.11 Requires Machining 0.01 Dimensional Tolerance (Inches) 0.1 0 0 50 100 150 200 250 300 350 400 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Temperature (F) Component Maximum Dimension (Inches)

SIZE LIMITATIONS AlBeCAST® COMPOSITE WALL THICKNESS The maximum casting charge weight using the largest For 0.60the purposes of this discussion, casting size refers coil and crucible is currently 80 pounds [36.3 kg]. to the outsideConsult dimensionsMaterion of the investment shell. 0.50 Based on the furnace capacity and on the feed ratios, The capability of casting larger castings under 30 the maximum casting weight that can be cast today pounds0.40 [13.6 kg] is limited by the physical size of Recommended Range is approximately 30 pounds [13.6 kg]. the furnace. The maximum casting size is approxi- mately0.30 20" x 20" [500 mm x 500 mm] for square designs,0.20 and 24" [600 mm] maximum diameter for circular designs. Ideal Range Consult Materion

Wall Thickness (Inches) 0.10 Not Recommended 0.00 0 2 4 6 8 10 12 14 16 18 20

Component Maximum Dimension (Inches) AlBeCAST® 910 COMPOSITE TENSILE PROPERTIES VS TEMP AlBeCAST® 910 COMPOSITE COMPRESSIVE STRENGTH VS TEMP 35 7 25

30 6 20 25 5 15 20 4

15 3 10 Elongation % Strength (Ksi) 10 2 5 5 1 Compressive Yield Strength (Ksi) 0 0 0 -100 0 100 200 300 400 500 0 500 1000 1500 2000

Temperature (F) Temperature (F)

UTS YS ELONG

AlBeCAST® 910 COMPOSITE CTE VS TEMP AlBeCAST® 910 COMPOSITE AXIAL FATIGUE (R=-1) 10 14

9 20

8 16

7 12

6 Stress (Ksi) 8 CTE (ppm/°F)

5 4

4 0 -300 -200 -100 0 100 200 300 400 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09

Temperature (F) Cycles to Failure

AlBeCAST® 910 COMPOSITE POISSON’S RATIO VS TEMP AlBeCAST® COMPOSITE DIMENSIONAL TOLERANCE 0.16 WALL THICKNESS 0.08

One of the significant advantages of investment 0.07 0.15 If section thickness variation is unavoidable, a gradual casting is the ability to produce relatively thin casting change0.06 in sectionRecommended thickness is preferable. This enables 0.14 wall thicknesses. Ribbed walls offer further enhanced solidification0.05 to be easily controlled, resulting in stiffness to the part and improved metal feeding for a cleaner casting. 0.13 0.04 the casting process. Consult Materion Sharp0.03 corners and intersections can lead to unsound 0.12

Poisson’s Ratio Some casting designs that require wall thickness conditions and poor structural characteristics in 0.02 0.11 greater than 0.500 inches [12.5 mm] can be difficult aluminum beryllium castings. TheRequires use Machining of fillets and radii to cast without inherent solidification defects. is critical0.01 to avoid hot spots and shrinkage. The typical Dimensional Tolerance (Inches) 0.1 0 ® 0 Aluminum50 100 beryllium150 200 components250 300 350with 400cast features minimum0 radii2 4 recommended6 8 10 12 14 for16 AlBeCast18 20 22 24 material26 28 30 greater than 1" [25 mm] in thickness have been is 0.06" [1.5 mm]. Temperature (F) Component Maximum Dimension (Inches) produced. However, wall thickness greater than In view of the need for uniform wall thickness, multiple 0.500" [12.5 mm] is not recommended without intersecting features should be offset from one another prior design review with Materion. to prevent hot spots and shrinkage at the junction. Wall thickness tolerances can be controlled by the

amount of support provided in the design to eliminate AlBeCAST® COMPOSITE WALL THICKNESS flexing during wax fabrication, mold manufacturing 0.60 and casting solidification. The recommended toler- Consult Materion ance increases in relation to the size of the wall area. 0.50

The greatest amount of wall thickness shrinkage will 0.40 occur in the mid-span or half the distance between Recommended Range ribs or supporting geometry. A wall thickness toler- 0.30

ance at the supported end can usually be maintained 0.20 at ± 0.004" [± 0.1 mm] and decrease as a function Ideal Range Consult Materion of the unsupported distance. Wall Thickness (Inches) 0.10 Not Recommended Wall thickness should be kept constant if possible. 0.00 Variation in section thickness may lead to poor feeding 0 2 4 6 8 10 12 14 16 18 20 conditions and result in hot spots or shrinkage. Component Maximum Dimension (Inches)

MINIMUM PREFERRED MINIMUM PREFERRED CASTING CASTING SIZE WALL WALL WALL WALL SIZE THICKNESS THICKNESS THICKNESS THICKNESS 0" - 10" 0.06" 0.08" - 0.12" 25 mm - 250 mm 1.5 mm 2 mm – 3 mm 10" and up 0.09" 0.12" - 0.25" 250 mm and up 2.25 mm 3 mm – 6 mm FILLETS AND RADII Larger fillet and corner radii are required in aluminum micro-shrinkage and heat affected zone defects beryllium castings in comparison to conventional at corners. Recommended fillet and corner radii investment cast aluminum alloys due to the solidifica- are 0.06" [1.5mm] minimum, however larger is tion rate differences between the materials. typically preferred. The larger fillet and corner radii will minimize

CAST HOLES OR CAVITIES Holes from 0.25" [6 mm] diameter and larger can Long holes with small diameters will form weak be cast directly in AlBeCast® material with a maxi- ceramic cores during the shell process. These weak mum through-hole depth less than or equal to their cores have a tendency to break during casting, leaving diameter. Holes larger than 1.5" [38 mm] diameter excess metal in the hole and shell fragments in other may have increased depth, however, please review areas of the casting. In addition, removing shell mate- with Materion. rial from long narrow passageways will add extra time Maximum blind hole depth is half of the holes and labor to remove the shell. Therefore machining diameter. In some cases, it is more cost effective the holes later may prove more cost effective. to produce these features by machining after casting Tapered holes or cavities can be produced, however, due to the position variability of casting directly. The the direction of the hole or cavity taper will greatly roundness of cast holes is influenced by the material influence the cost of tooling. Positive tapers are more surrounding it. If the mass of material around the economical since tooling cost is lower while negative hole is uneven, the hole roundness will decrease. tapers prevent removal of wax patterns directly and require complex tooling.

SURFACE FINISH Typical surface roughness on aluminum beryllium Rapid prototypes and soft tool fabricated patterns castings is less than 175 RMS using wax injection will have typical surface finishes of 175 RMS or greater. tooling. When a surface finish less than 175 RMS is The increase in surface roughness must be considered required, machine stock may be added to the casting when using these pattern fabrication methods. design to accommodate for a machining operation. This highlights the need for a review of critical surfaces early in the design process, so that machine stock may be incorporated in the casting design. ANGLES MACHINING Angular tolerances of +/- 0.5 degrees are normal. AlBeCast material is fabricated using processes which mirror standard aluminum industry prac- DRAFT tices. Machining, joining, bending and coating Investment casting does not require any draft operations can all be conducted on this material. tolerance. The principle difference between aluminum and aluminum-beryllium materials during these operations ROUNDNESS is the need to control, collect, and remove any General linear tolerances may be held for diameter. beryllium-containing particles generated during the fabrication operations. CONCENTRICITY AlBeCast composites can be conventionally machined The general section thickness tolerance applies using standard high-speed steel cutters. Standard for concentricity. feeds and speeds may be used, but due to the abrasive nature of the beryllium, the material is more abrasive SPECIFICATIONS than aluminum alloys. Cutter life is approximately Materion's AlBeCast® product line consists of three 60 percent of that expected for similar cuts in product specifications; Aerospace, Commercial and aluminum. For that reason, carbide cutting tools Prototype. These specifications define the required are recommended. Using standard geometry C-2 properties, inspections and quality assurances for tungsten carbide cutting tools, machining speeds their respective grade. These specifications will be as high as 600 surface feet per minute [183 m/min] provided upon request to Materion. with a 0.006" [0.15 mm] chip load have been used with success in milling operations. Machining with coolants is recommended and most coolants suitable for aluminum can be used with AlBeCast composite. It may be required to stress relieve components during or after machining. A simple stress relief of 500°C [925°F] for two hours followed by a furnace cool is sufficient to remove these stresses. Mechanical properties are unchanged by this process.

FASTENING Inserts and pinning are compatible with AlBeCast material. Aluminum insert information should be used, with the usual care taken near edges to avoid breakout. Inserts should be installed as part of the machining and finishing process. COATING Protective and cosmetic coatings can be placed witness coupons should be used for any new coating on aluminum beryllium castings. Aluminum industry and/or coating source. New coatings are always standards are used to specify the coating. In addition being tested. to alloy compatibility, successful coating of any metal The following AlBeCast® material finishes have depends on other variables, including cleanliness, been tested in a salt fog chamber in accordance coating source and processing sequence. Test and with ASTM standard B117 (5 percent salt solution, 95°F (35°C), 336 Hrs).

SALT FOG WT. CHANGE COATING TYPE SPECIFICATION (MG/CM2 ) Chromate Conversion MIL-C5541E, Class 1a 0.3 @ 336hr. Chromate Conversion MIL-C-5541E, Class 3 1.3 @ 336hr. Non-Chromate Conversion Safeguard CC-3000 0.7 @ 336hr. Chromic Anodize dyed and sealed MIL-A-8625 (seal) 1.8 @ 336hr. Electroless Nickel MIL-C-26074E 0 @ 336hr. Teflon-sealed Electroless Nickel MIL-C-26074E -0.25 @ 336hr. Entraco Process Electroless Nickel Entraco Process <0.1 @ 336hr. Aluminum Plating Alumiplate 0 @ 336hr. Aluminum Plate, Black Anodize Alumiplate, and MIL-A-8625F 0 @ 336hr. Primer BR-127 0 @ 336hr. Organic/Inorganic Finish Available upon request <1.0 @ 336hr.

HEALTH AND SAFETY Materion provides safety information for a variety information you need, please contact us or call the of their products and materials. Find information on Materion Information Hotline at +1.800.862.4118. Environmental Health & Safety (EH&S) including Materion Corporation requests can be called FAQs about Beryllium, Safety Facts and Materion's in to the Hotline listed above, or emailed to EH&S Policies on our website and search our library of [email protected] Safety Data Sheets. If you cannot find the safety Contact Information For more information, please call 419-862-4216 or visit materion.com/AlBeCast