DOCSLIB.ORG

Laser Surface Structuring of Cemented Carbide for Improving the Strength of Induction Brazed Joints

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Laser Surface Structuring of Cemented Carbide for Improving the Strength of Induction Brazed Joints Journal of Manufacturing and Materials Processing Article Laser Surface Structuring of Cemented Carbide for improving the Strength of Induction Brazed Joints Ammar Ahsan * , Igor Kryukov and Stefan Böhm Fachgebiet Trennende und Fügende Fertigungsverfahren (tff), Universität Kassel, Kurt-Wolters-Str. 3, 34125 Kassel, Germany; [email protected] (I.K.); [email protected] (S.B.) * Correspondence: [email protected]; Tel.: +49-561-804-7702 Received: 1 April 2019; Accepted: 29 May 2019; Published: 3 June 2019 Abstract: The effect of micro patterning of cemented carbide surface using nanosecond diode pumped solid-state pulsed laser on the strength of induction brazed carbide and steel joints has been investigated. Surface patterns increase the total surface area of the joint and, for an originally hydrophilic surface, increase the wettability of a liquid on a solid surface such that, instead of building droplets, the liquid spreads and flows on the surface. Microcomputed tomography (µ-CT) was used to observe the filler/carbide interface after brazing and to analyze the presence of porosity or remnant flux in the joint. Microstructures of the brazed joints with various surface patterns were analyzed using scanning electron microscopy. The strength of the joints was measured using shear tests. Results have shown that the groove pattern on the surface of carbide increases the joint strength by 70–80%, whereas, surface patterns of bi-directional grooves (grid) reduced the joint strength drastically. Dimples on the carbide surface did not show any improvement in the strength of the brazed joints compared to samples with no surface pattern. Keywords: brazing; carbide; surface structuring; laser ablation 1. Introduction Geometrically defined polycrystalline diamond (PCD) saw tips with a backing layer of cemented carbide (WC-Co) represent an alternative to sintered diamond blades with geometrically undefined cutting edges for sawing of natural stones like granite, marble etc. [1–3]. It has been shown that using a high negative rake angle on the saw tips, which is advantageous for reduction of tool wear, results in failure in the brazed joints of the saw tips [1]. The saw tips used particularly on the band saws, because of their small size, cannot be screw clamped to the tool body as in the case of a typical indexed milling cutter. Brazing is the most common process of joining carbide or carbide backed PCD tips to the body of the saw blades. Most of the sawing tools are still brazed in an air atmosphere with an oxy-acetylene flame or an induction coil. However, the strength of the brazed joints varies widely because of various factors such as filler metal composition [4], gap thickness [5], brazing time and temperature [6], surface roughness [7], surface chemical composition [8–10], cleanliness of the surface, incomplete removal of oxides and inclusions of flux, presence of porosity, and thermal cracks [11]. Tungsten carbide, especially the grades with high hardness and low binder content, shows poor wettability by most brazing alloy standards, especially when brazing in air [12,13]. The filler metal forms a metallic bond with the metal (binder) present on the surface and for carbide grades containing low binder content, the surface contains very little binder for the filler metal to form a bond with. The state-of-the-art solution is the galvanic coating of the carbide surface with a metal usually cobalt or nickel (metalizing). However, due to the health and safety issues the electrolytes used in the process are classified as hazardous substances by the European Union (EU) and their production and application will be gradually limited [14–16]. A novel approach for enhancing the wettability of the surfaces is J. Manuf. Mater. Process. 2019, 3, 44; doi:10.3390/jmmp3020044 www.mdpi.com/journal/jmmp J. Manuf. Mater. Process. 2019, 3, x FOR PEER REVIEW 2 of 11 J. Manuf. Mater. Process. 2019, 3, 44 2 of 11 production and application will be gradually limited [14–16]. A novel approach for enhancing the thewettability process of of the “laser surfaces structuring”. is the process Whereby of “laser the surface structuring”. of the materialWhereby is the ablated surface using of the Nano-, material pico-, is orablated femtosecond using Nano pulsed‐, pico lasers‐, or sofemtosecond as to generate pulsed specific lasers surface so as to textures generate to specific achieve surface desirable textures optical, to electricalachieve desirable or mechanical optical, characteristics. electrical or mechanical Recent studies characteristics. have shown Recent the potential studies ofhave this shown technique the topotential improve of thethis wettabilitytechnique to of improve ceramic the [17 wettability] as well as of metallic ceramic materials [17] as well [18 as]. metallic Zhang et materials al. used [18]. this techniqueZhang et al. to used improve this technique wettability to characteristics improve wettability (and in characteristics turn the joint (and strength) in turn of the Al2 Ojoint3 surface strength) for brazingof Al2O3 with surface stainless for brazing steel under with vacuumstainless [ 19steel]. It under was shown vacuum that [19]. the surfaceIt was shown grooves that not the only surface cause mechanicalgrooves not pinningonly cause at the mechanical ceramic/ fillerpinning interface, at the ceramic but also / result filler ininterface, periodic but tensile also result and compressive in periodic residualtensile and stress compressive peaks, which residual hinder stress crack peaks, propagation. which hinder Similarly, crack propagation. Otero et al. Similarly, generated Otero grooves et al. andgenerated dimple grooves structures and ondimple a Nimonic structures N75 on alloy a Nimonic surface andN75 studied alloy surface the eff andect ofstudied surface the structures effect of onsurface wettability structures and on joint wettability strength and [20]. joint The strength results showed [20]. The a 2–2.5results increaseshowed ina 2–2.5x the shear increase strength in the of × brazedshear strength joint. However, of brazed this joint. technique However, has this not technique been tried has on tungstennot been tried carbide on/ steeltungsten brazed carbide/steel joints and specificallybrazed joints air and atmosphere specifically brazed air joints.atmosphere This work brazed is intended joints. This to enhance work is the intended strength ofto theenhance uncoated the tungstenstrength of carbide the uncoated/steel brazed tungsten joints carbide/steel by structuring brazed the surface joints by of thestructuring carbide usingthe surface a short-pulsed of the carbide laser. Furthermore,using a short‐ computerpulsed laser. tomography Furthermore, is used computer as a non-destructive tomography testing is used approach as a non to‐destructive assess the qualitytesting ofapproach the brazed to assess joints. the quality of the brazed joints. Pulsed Laser Ablation Laser ablation refers to the material removal by using short high-intensityhigh‐intensity laser pulses as the heating source. Pulsed Pulsed lasers lasers produce produce shorter shorter bursts bursts of of energy, energy, which result in much higher peak energy levels than a continuouscontinuous wave (CW) laser source [[21].21]. Pulse durations may be in micro-micro‐ or nanoseconds (short pulses) or in pico-pico‐ and femtoseconds (i.e.,(i.e., ultra-shortultra‐short pulses).pulses). For pulse durations above 10 picoseconds (ps), the ablation process consists of heat conduction, melting, evaporation and and plasma plasma formation formation as as shown shown in in Figure Figure 11 [22].[ 22 ].Pulse Pulse durations durations of ofless less than than 10 10ps ps(ultrashort (ultrashort pulses) pulses) are areshorter shorter than than the time the time required required for electrons, for electrons, which which absorb absorb the energy the energy of the ofphotons, the photons, to transfer to transfer their energy their energy to the tolattice. the lattice. Therefore, Therefore, ablation ablation processes processes with ultrashort with ultrashort pulses pulsesinvolve involve no melting no melting and virtually and virtually no heat no heataffected affected zone zone [23]. [ 23Although]. Although ultrashort ultrashort laser laser ablation ablation is isextremely extremely precise, precise, the the ablation ablation rate rate is is significantly significantly lower lower than than with with laser laser ablation ablation in in a nanosecond regime, which allows thethe highest ablationablation eefficiencyfficiency [[22].22]. Figure 1. Pulsed laser beam and matter interaction ( a) short pulse laser ( μµs, ns)—matter interaction; (b) ultrashort pulse (ps,(ps, fs)fs) beam-matterbeam‐matter interactioninteraction [[22].22]. 2. Materials and Methods 2. Materials and Methods For this work, tungsten carbide (WC-8%Co) type K-20F (ISO K20-K30) with a grain size of 0.7 µm For this work, tungsten carbide (WC‐8%Co) type K‐20F (ISO K20‐K30) with a grain size of from HHT-Hartmetall, Germany, was used in a cylindrical form with a 9 mm diameter and 10 mm 0.7 μm from HHT‐Hartmetall, Germany, was used in a cylindrical form with a 9 mm diameter and height. These were brazed on to 20 mm diameter and 15 mm high cylinders made of S235JR steel. 10 mm height. These were brazed on to 20 mm diameter and 15 mm high cylinders made of S235JR Both carbide and steel parts were sand blasted using 10 µm corundum particles and then cleaned in steel. Both carbide and steel parts were sand blasted using 10 μm corundum particles and then an ultrasonic bath of ethanol. Sand blasting was necessary as the carbide surface in an ‘as-delivered’ cleaned in an ultrasonic bath of ethanol. Sand blasting was necessary as the carbide surface in an condition was oxidized and had a pale-yellow tint most likely due to the presence of tungsten oxide ‘as‐delivered’ condition was oxidized and had a pale‐yellow tint most likely due to the presence of on the surface. The roughness of the blank surface after sand blasting and ultrasonic cleaning was tungsten oxide on the surface. The roughness of the blank surface after sand blasting and ultrasonic measured optically using white light interferometry and the roughness parameters were found to be J.
Load more

Recommended publications
  • What Is Cemented Carbide? the History of Cemented Carbide
    THE DESIGNER’S GUIDE TO TUNGSTEN CARBIDE THE DESIGNER’S GUIDE TO TUNGSTEN CARBIDE Chapter I - Background What is cemented carbide? Tungsten carbide (WC), also referred to as cemented carbide, is a composite material manufac- tured by a process called powder metallurgy. Tungsten carbide powder, generally ranging in proportion between 70%-97% of the total weight, is mixed with a binder metal, usually cobalt or nickel, compacted in a die and then sintered in a furnace. The term “cemented” refers to the tungsten carbide particles being captured in the metallic binder material and “ cemented” together, forming a metallurgical bond between the tungsten carbide particles and the binder (WC - Co), in the sintering process. The cemented carbide industry commonly refers to this material as simply “carbide”, although the terms tungsten carbide and cemented carbide are used interchangeably. If the permanent deformation of a material at failure is quite small, the material is labeled brittle; if the plastic deformation is very large, the material is called ductile. Carbide is classified techni- cally as a “brittle” material since it exhibits little or no plastic deformation preceding the initiation of a crack and total failure. Without the presence of the metallic binder phase, tungsten carbide could be considered a ceramic material much the same as silicon carbide or aluminum oxide. The definition of a ceramic material is the marriage of a metal to a nonmetal, for example silicon (metal) carbide (carbon, nonmetal), aluminum (metal) oxide (oxygen, non-metal), or silicon ni- tride. A cermet is a composite material composed of ceramic (cer) and metallic (met) materials.
    [Show full text]
  • Effects of Vanadium Carbide on Sintered WC-10%Co Produced By
    Sains Malaysiana 44(8)(2015): 1175–1181 Effects of Vanadium Carbide on Sintered WC-10%Co Produced by Micro-powder Injection Molding (Kesan Vanadium Karbida ke atas WC-10%Co Bersinter dihasilkan melalui Pengacuan Suntikan Serbuk Mikro) WONG YEE NING, NORHAMIDI MUHAMAD, ABU BAKAR SULONG*, ABDOLALI FAYYAZ & MUHAMMAD RAFI RAZA ABSTRACT Ultrafine, cemented tungsten carbide (WC) possesses exceptional hardness, wear resistance and high strength in various applications. In this study, WC was produced through micro powder injection molding (μPIM), which is also applicable for metals and ceramics in producing complex parts with high-dimensional accuracy. Different inhibitors, such as VC, Cr2C3, NbC, or TaC, were added to improve the mechanical properties of WC and control its grain growth. The effects of a grain growth inhibitor were investigated by adding VC in WC–10%Co–nVC, where n = 0 to 1.2 wt. %. The mechanical properties of the sintered part, such as hardness and flexural strength, were determined. The morphology and elemental distribution of the samples were studied by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. X-ray diffraction was employed to study the phases of the obtained samples. The results showed that the sample with 0.4 wt. % VC (optimal amount) sintered at 1410°C exhibited the highest theoretical density, hardness and flexural strength of 95.2%, 1973±31HV and 2586±172 MPa, respectively. The average grain size measured was 519±27 nm. VC acted as a grain growth inhibitor during sintering, thereby improving the mechanical properties. Keywords: Flexure strength; grain growth inhibitor; microstructure; micro powder injection moulding; XRD ABSTRAK Ultra halus, tungsten karbida terikat (WC) memiliki ciri kekerasan yang tinggi, rintangan haus dan kekuatan yang tinggi dalam pelbagai aplikasi.
    [Show full text]
  • Ultra-Tool Speeds & Feeds Technical & Application Information
    Tech Flyer v2020.1 High-Performance Solid Carbide Round Tools Technical & Application Information ® American Made PERFORMANCE American Designed SERIES American Owned 2 rev2020.1 e v o l v e • • r e SOLID e v CARBIDE s l o o l v v n e i 19 T E A M 72 HUNTINGTON American Made BEACH American Designed American Owned Creating Value through Efficiency by utilizing progressive Quality, Manufacturing, Human Resource & Technological applications. SmoothFlute Patented Variable Helix design for robust stability in deep axial cuts SmoothGrind SmoothCoat Polished cutting surfaces Sputter-based SuperNitride for extreme sharpness PVD coating for superior surface and lubricity hardness & uniformity SmoothC ntricity Precision grinding, tool holding, SmoothEdge and tolerances for minimized TIR Surface and edge preparation for lubricity and minimized tool break-in -Grain® Laser etching for permanent ® ntilate. The World’s finest, purest toolVe identification sub-micron tungsten carbide powders Designed & Manufactured in the USA • ultra-tool.com ar safety glasses. Read MSDS. We r. of California to cause cancer (Proposition 65). RNING: Grinding causes hazardous dust. ols may shatte This product contains a chemical known to the State To WA Tight tolerance shanks with superior roundness are shrink-fit ready . e . Sales offices in ® ntilate Ve Florida & California Process control ID# on Designed & Manufactured in the USA • ultra-tool.com Made in the USA for 45 years ar safety glasses. Read MSDS. We product label ensures r. Performance Guaranteed total traceability
    [Show full text]
  • High-Temperature Wear of Cemented Tungsten Carbide Tools While Machining Particleboard and Fiberboard
    J Wood Sci (1999) 45:445-455 © The Japan Wood Research Society 1999 Jamal Y. Sheikh-Ahmad • John A. Bailey High-temperature wear of cemented tungsten carbide tools while machining particleboard and fiberboard Received: March 10, 1999 / Accepted: May 31, 1999 Abstract Published research on the wear processes of ce- For almost three decades the use of cemented tungsten mented tungsten carbide tools used for machining reconsti- carbide cutting tools in the wood-working industry has pro- tuted wood products was reviewed, and the current state of vided significant improvements in tool life, primarily be- knowledge in this area was evaluated. Underlying assump- cause of the superior hardness of these alloys compared to tions and conclusions regarding high-temperature oxida- that of carbon steels, tool steels, and cast cobalt alloys (e.g., tion/corrosion wear during machining were examined in stellite). The improvement in tool life has been particularly view of known reaction kinetics of cemented tungsten significant in machining abrasive materials, such as silica- carbide alloys in oxidative and corrosive environments at containing tropical wood species (e.g., melapi) and reconsti- temperatures that may occur at the cutting edge. This ex- tuted wood products (e.g., particleboard and fiberboard). amination indicated that some wear mechanisms other than Cemented tungsten carbides are most commonly used in high-temperature oxidation/corrosion are likely to be rate- the wood-working industry as tipping material and inserts controlling when machining reconstituted wood products for circular saws and peripheral milling machines. Despite such as particleboard and fiberboard. their wide use, little is known concerning their wear behav- ior, especially in the high-speed machining of reconstituted Key words Cemented tungsten carbide • Machining • Wear wood products.
    [Show full text]
  • SILVER BRAZING FILLER METALS for TUNGSTEN CARBIDE and PCD for Brazing Tungsten Carbide and Tungsten Carbide Backed Poly-Crystalline Diamond Pieces
    Metal Joining SILVER BRAZING FILLER METALS FOR TUNGSTEN CARBIDE AND PCD for brazing tungsten carbide and tungsten carbide backed poly-crystalline diamond pieces CONTENTS PRODUCTS AT A GLANCE Products at a glance 2 Compositions TM For Brazing Tungsten Carbide and 3 Argo-braze products Alloy System Ag Cu Zn Ni have the following Poly-crystalline Diamond compositions: Additional Elements Mn In Tri-foil Products For Brazing 4 Tungsten Carbide Standard products are supplied to conform to ISO17672. Special products conform to proprietary Johnson Matthey specifications. Recommended Uses For These 5 TM Argo-braze Products Uses for the Products Technical 5 TM These Argo-braze products are most commonly used to form joints on a combination of the following Key 7 materials: Tungsten carbide and tungsten carbide backed poly-crystalline diamond Carbon/low alloy, tool and stainless steel* Note: *Special considerations apply if stainless steel joints are exposed to water in service Other materials such as cast iron and aluminium bronze Conditions for Use The Argo-brazeTM products are intended for use by brazing in air using a hand torch, fixed burner system, high frequency induction or resistance heating method. They should be used with a compatible brazing flux. This can be introduced to the joint by applying a separate flux powder or paste, or a brazing paste with a flux binder system. 2 Metal Joining products FOR BRAZING TUNGSTEN CARBIDE AND POLY-CRYSTALLINE DIAMOND These products have been formulated as brazing filler metals for the joining of tungsten carbide or poly-crystalline diamond pieces where the greatest dimension does not exceed 20mm.
    [Show full text]
  • Ceramic End Mill Comparison with Inconel®718
    TOOL NEWS B228A Ceramic End Mills CERAMIC Corner Radius End Mills Ultra high productivity for nickel based heat resistant alloys CERAMIC Ceramic End Mills CERAMIC Corner Radius End Mills From diffi cult-to-cut to easy-to-cut! Generation of cutting heat theory Feature of Ni based heat-resistant alloy Ni based difficult-to-cut heat resistant alloys such Tensile strength as Inconel®718 soften at temperatures exceeding 1472ºF. At these temperatures, difficult-to-cut Bearing materials become easier to machine because their bearing and tensile strengths are lowered. Ceramic end mills can work effectively at these high temperatures and self generate the heat required to soften the machined material through Tensile Strength, Tensile Bearing strength [Mpa] ultra-high feeds and speeds. Temperature 1472°F High temperature hardness of cemented carbide and ceramic Ceramic Cemented carbide end mills whose material strength is significantly reduced in a temperature Cemented carbide zone exceeding 1472ºF, cannot increase machining speed and perform large depth of cut machining at high temperatures, in contrast ceramic end mills can preform machining at Hardness[Hv] high temperatures because the strength is not reduced even at 1472°F. Temperature 1472°F 1 Features Seamless grinding technology Optimum ceramic grade for provides greater chipping resistance Heat Resistant Super Alloy even during extreme roughing applications. applications Optimized helix angle to reduce cutting force and to prevent pull-out during milling. 4-flute type for pocketing and slotting,
    [Show full text]
  • Cemented Carbidescarbides Forfor Powderpowder Metalmetal Toolingtooling Applicationsapplications
    AdvancedAdvanced CementedCemented CarbidesCarbides forfor PowderPowder MetalMetal ToolingTooling ApplicationsApplications Dr. Leonid I. Frayman Chief Metallurgist 41th Anniversary 41th Anniversary Presented at MPIF “PM Compacting & Tooling” 1968-2009 1968-2009 Seminar (October 27-28, 2009. Cleveland, OH.) CARBIDES?… ……WWhhaatt ddoo wwee kknnooww aabboouutt tthheemm?? Agenda: What is a cemented carbide? Why do we use cemented carbide in PM? What advancements have been made for PM tooling applications in: - carbide processing and manufacturing? - carbide grade development? - carbide failure analysis and troubleshooting? WhatWhat isis CementedCemented Carbide?Carbide? Definition: Cemented Carbide is a composite material of a soft binder metal usually either Cobalt (Co) or Nickel (Ni) or Iron (Fe) or a mixture thereof and hard carbides like WC (Tungsten Carbide), Mo2C (Molybdenum Carbide), TaC (Tantalum Carbide), Cr3C2 (Chromium Carbide), VC (Vanadium Carbide), TiC (Titanium Carbide), etc. or their mixes. Carbides: Selected Mechanical Properties. Carbide Vickers (HV) Hardness @ Various Rockwell Hardness Ultimate Compressive Transverse Modulus of Formula Temperatures, oC (oF) @ Room Strength, Rupture Strength, Elasticity, Temperature, MPa (ksi) MPa (ksi) GPa (106 ksi) 20 oC (78 oF) 730 oC (1350 oF) HRa TiC* 2930 640 93 1330-3900 (193-522) 280-400 (40.6-58.0) 370 (52.9) HfC* 2860 - 84 - - - VC* 2800 250 83 620 (89.9) 70 (10.1) 360 (51.4) NbC 2400 350 83 1400 (203) - 270 (38.5) * TaC* 1570 800 82 - - 470 (68,2) - - 81 100 (14.5) 170-380 ((24.7-55.1) 280 (40.0) Cr3C2* - - 2700 (392) 50 (7.3) Mo2C* 74 375 (53.6) WC* 2400 280 81 2700-3600 (392-522) 530-560 (76.9-81.2) 665 (95) *NOTE: TiC-Titanium Carbide; HfC-Hafnium Carbide; VC-Vanadium Carbide; NbC-Niobium Carbide; TaC-Tantalum Carbide; Cr3C2 - Chromium Carbide; Mo2C - Molybdenum Carbide; WC-Tungsten Carbide.
    [Show full text]
  • Machining Recommendations WHAT IS TOOLOX?
    Machining Recommendations WHAT IS TOOLOX? Toolox® is a modern quenched and tempered prehardened engineering and tool steel, delivered with measured and guaranteed mechanical properties. The basic idea is to save you time by delivering Toolox heat treated and ready to use. It provides you with lower costs, reduced risks and saves you valuable time in your production process due to its excellent machinability. This combined with the benefit of working with the hardest prehardened tool steel in the world gives you a simple to use material with a wide variety of uses. Toolox is based on the same low carbon content as in Hardox® and Strenx®, but it is specially developed for tools and machine components working at high temperatures. It has excellent fatigue properties, and you can increase the surface hardness with nitriding or PVD coatings to gain more control over the service life of your tools or components. In the information that follows, you will find our recommendations of tools to process Toolox. Similar tools from other suppliers might work, but here are the ones we have tested so far. SHORTER LEAD TIME FROM CONCEPT TO PRODUCTION 1. Your customer has an idea 2. Manufacturing 3. Transport 4. Quenching and tempering 5. Adjusting 6. Production 2 WHAT IS TOOLOX? DRILLING RECOMMENDATIONS HSS DRILLS Use only HSS drills when you have unstable machine conditions. If the machine conditions are good you can use different solid/brazed cemented carbide drill or drills with exchangeable heads. HSS-Co Use an HSS-Co HSS Individual holes can be drilled drill (8% Co) with a HSS-E with an ordinary HSS drill.
    [Show full text]
  • Performance of Coated Carbide Tools
    The International Journal Of Engineering And Science (IJES) ||Volume||2 ||Issue|| 6 ||Pages|| 47-54||2013|| ISSN(e): 2319 – 1813 ISSN(p): 2319 – 1805 Performance of Coated Carbide Tools M. Narasimha1,R. Reiji Kumar2, Achamyelehaemro Kassie3 1,2,3School of Mechanical and Industrial Engineering, Bahir Dar University, Bahir Dar, Ethiopia, , ------------------------------------------------------ABATRACT---------------------------------------------------------- There are different types of cutting tools in use for machining various materials for the multiple operations in order to produce components.The manufacturers of these components expect to improving their productivity, quality of the components and longer life of the cutting tools. Similarly the customers also expect the quality and durability of the product at competitive price.The tool manufacturers also aims at producing quality tools to with stand for higher cutting forces, thermal resistivity with more wear resistance and to give longer life of the tool, to produce better surface finish product and maintain desired dimensional accuracies of the product. For the past several years the materials of the cutting tools are the same, but due to continuous improvements in enhancing the life of the cutting tools, different methods/process are in progress for producing the tools. The cutting tool manufacturers with their rich R&D experience and continuous innovations, carrying on their production activity to meet the challenges of the market demand. In this paper the analysis is made for the performance of various coated carbide cutting tools in machining the steel AISI 1018. In this review, the machining performance of coated tungsten based cemented carbides, were investigated during finish turning of AISI 1018 steel under dry conditions.
    [Show full text]
  • Insert Grades Grades Insert A1 to A37 a A
    Insert Grades Insert Grades A1 to A37 A A A Grades for Turning …………………………………… A2 Grades for Milling …………………………………… A3 Grade Comparison Chart (CVD / PVD Coated Grades) ……………………… A4 (Cermet, Cemented Carbide, Ceramic) ………… A6 (CBN, Polycrystalline Diamond) ………………… A7 Chipbreaker Comparison Chart …………………… A8 Chipbreaker and Grade Selection Guide for Turning For Steel Turning ………………………………… A10 For Stainless Steel Turning …………………… A14 For Cast Iron turning …………………………… A16 For Exotic Alloy Turning ………………………… A18 For Hardened Steel Turning …………………… A20 For Non-Ferrous Metal Turning ……………… A22 For Small Lathes ………………………………… A24 Coated Carbide …………………………………… A26 Cermet ……………………………………………… A29 Cemented Carbide ………………………………… A30 CBN ………………………………………………… A32 Polycrystalline Diamond ………………………… A34 Ceramic …………………………………………… A36 Material Properties ……………………………… A37 A1 Grades for Turning Work Material General Steel (Carbon Steel, Alloy Steel), Mild Steel Stainless Steel Cast Iron Wear Resistance Fracture Resistance Wear Resistance Fracture Resistance Wear Resistance Fracture Resistance Classification Q P01 P10 P20 P30 P40 Q M01 M10 M20 M30 M40 Q K01 K10 K20 K30 AC8015P C AC6020M C AC4010K C C AC8020P AC6030M C AC4015K C C AC8025P C AC6040M AC420K C P Insert Grades AC8035P Coated Carbide C C C C AC610M AC630M AC8025P AC810P C A AC820P C AC405K C C A26 AC830P AC415K AC1030U AC1030U AC1030U For Small Lathes P P P A24 P AC530U P AC530U P AC530U P T1500Z Coated T2500Z Cermet P A29 P T3000Z T1000A T1000A Cermet T1500A T1000A T1500A A29 T2500A Cemented Carbide
    [Show full text]
  • Microstructure Investigations of WC-Co Cemented Carbide Containing ɳ-Phase and Cr
    ISSN: 1401-5773. UPTEC Q 18024 Examensarbete 30 hp Juni 2018 Microstructure investigations of WC-Co cemented carbide containing ɳ-phase and Cr Sofia Tran Mikrostruktur utredning av hårdmetall innehållande η-fas och Cr Sofia Tran Hårdmetaller består ofta av WC och Co. Hårdmetallen produceras genom att sintra pulver av de önskade elementen. I detta fall är elementen W, C och Co. Sintring är en process som sammanfogar fasta partiklar till större objekt. I en hårdmetall av WC och Co, brukar WC kallas för den hårda fasen och Co för bindefas, då Co smälter vid uppvärmningen och binder ihop de fasta WC-kornen som ett lim när de har stelnat. Den hårda fasen är generellt det som ger materialet dess hårdhet och bindefasen, dess slagseghet. För skärande bearbetning av material som stål, används skär av hårdmetall då de har en bra kombination av hårdhet och seghet. Ett exempel på en skärande bearbetningsmetod är fräsning, där man använder sig av roterande skär för att avverka material på arbetsmaterialet. Det är viktigt att skäret har en högre hårdhet än arbetsmaterialet för att skäret ska kunna avverka materialet. Skären måste även ha egenskaper som motstånd mot nötning och hög slagseghet samt hårdhet vid höga temperaturer. Detta är egenskaper som krävs för att skäret inte ska förlora sin prestanda under bearbetning samt att den ska ha en längre livslängd. För att nå upp till dessa krav på skären till fräsningen, måste segheten vara hög vilket fås genom att öka innehållet av bindefasen i sammansättningen. Men detta brukar ofta leda till en lägre hårdhet i en WC-Co hårdmetall.
    [Show full text]
  • Niobium in Tool Steels and Cemented Carbides
    NIOBIUM IN TOOL STEELS AND CEMENTED CARBIDES Franz Jeglitsch Institute for Physical Metallurgy and Materials Testing University of Leoben Franz-Josef-Strasse 18 8700 Leoben, Austria Abstract Niobium is an element of high affinity towards carbon and forms a very stable carbide. Therefore it is well suited as a carbide-forming alloying element in the production of tool steels and hard metal alloys. This paper first deals with the metallurgical fundamentals, such as the influence of niobium on the solidification behaviour of high speed steels, segregation of the MC-carbides during solidification, effect of the solidification rate on the precipitation of mono- carbides, solubility of niobium in austenite, effect on secondary hardness, M2C decomposition and methods for the achievement of higher niobium-contents in high-speed steels. In a second part selected examples of use are referred to in the categories of high speed steels, hot working tool steels, cold working tool steels and steels for plastic moulds. A short summary of niobium in cemented carbide completes the paper. Introduction Niobium is an element in group 5a of the periodic table and, as do the elements vanadium and tantalum of the same group and the elements of groups 4a and 6a, it forms, together with small atomic elements such as carbon, nitrogen, boron and silicon, very stable carbides, nitrides, borides and silicides, which are classified as hard metal alloys. The hard metal alloys (and also NbC) are mainly metallically bonded, have free electrons with overlapping valence - and conduction band and are suitable electrical and thermal conductors. Their high bond energy results in a high modulus of elasticity and a high melting point.
    [Show full text]