Cold Work Tool Steel Research Articles

Enhancing Wear Behavior and Hardness of D5 Cold Work Tool Steel through TiCrN Multilayer Nanocoating via Physical Vapor Deposition

Enhancing Wear Behavior and Hardness of D5 Cold Work Tool Steel through TiCrN Multilayer Nanocoating via Physical Vapor Deposition

Cryogenic Treatment of Martensitic Steels: Microstructural Fundamentals and Implications for Mechanical Properties and Wear and Corrosion Performance.

Conventional heat treatment is not capable of converting a sufficient amount of retained austenite into martensite in high-carbon or high-carbon and high-alloyed iron alloys. Cryogenic treatment induces the following alterations in the microstructures: (i) a considerable reduction in the retained austenite amount, (ii) formation of refined martensite coupled with an increased number of lattice defects, such as dislocations and twins, (iii) changes in the precipitation kinetics of nano-sized transient carbides during tempering, and (iv) an increase in the number of small globular carbides. These microstructural alterations are reflected in mechanical property improvements and better dimensional stability. A common consequence of cryogenic treatment is a significant increase in the wear resistance of steels. The current review deals with all of the mentioned microstructural changes as well as the variations in strength, toughness, wear performance, and corrosion resistance for a variety of iron alloys, such as carburising steels, hot work tool steels, bearing and eutectoid steels, and high-carbon and high-alloyed ledeburitic cold work tool steels.

Surface quality enhancement of cold work tool steel by GOV (flow peening) process versus abrasive flow machining

Surface quality enhancement of cold work tool steel by GOV (flow peening) process versus abrasive flow machining

The influence of plasma nitriding process conditions on the microstructure of coatings obtained on the substrate of selected tool steels

This study presents the results of research into the influence of the time of the plasma nitriding process on the microstructure of the coatings obtained. Cold-work tool steels (60WCrV8, 90MnCrV8, 145Cr6), hot-work tool steel (X37CrMoV5-1) and high-speed tool steel (HS6-5-2) were selected as substrate material. The processes were carried out under industrial conditions using an Ionit device from Oerlikon Metaplas with variable process times of 2, 4 and 6 hours. According to literature data, a nitriding mixture consisting of 5% nitrogen and 95% hydrogen was chosen, which allowed the expected diffusion layer to be obtained without a white layer (composed of iron nitrides). Analysis of elemental mapping indicates that the presence and content of nitride-forming elements influences the formation of alloy additive nitrides in the microstructure of the diffusion layer. It was also found that an increase in the duration of plasma nitriding, results in an increase in the depth of the nitrided layers formed on the substrate of high-alloy steels: X37CrMoV5-1 and HS6-5-2. Nitrides of alloying additives, present in the diffusion layer, are formed in the high-alloyed the hot-work steel X37CrMoV5-1, indicating that these steels are the most suitable for plasma nitriding of the entire tool steels analysed.

The Impact of Tempering Temperature on Retained Austenite and Mechanical Properties of 1.2842 Tool Steel

This work investigates the impact of tempering temperature on the mechanical properties quenched 1.2842 (O2) cold work tool steel depending on the volume fraction of retained austenite (RA). The tempering temperature significantly influences proportion of RA and the mechanical properties. Therefore, the tempering temperature and the volume fractions of RA in through-hardened tool steels must be optimized to minimize dimensional variations and augment performance in service. In this work, the hardened samples were subjected to tempering process at different tempering temperatures and hardnes, impact and tensile tests were applied to the samples. Then the results obtained from these tests were analyzed and optimum tempering temperature was defined. The findings reveal that low-temperature tempering leads to a robust stabilization of the RA phase and better mechanical properties for the steel investigated.

The Influence of Industrial-Scale Pack-Boroding Process Time on Thickness and Phase Composition of Selected Cold-Work Tool Steels

The Influence of Industrial-Scale Pack-Boroding Process Time on Thickness and Phase Composition of Selected Cold-Work Tool Steels

ANALYSIS OF THE INCLINATION OF SLOTS IN TEXTURED CERAMIC TOOLS THROUGH THE STUDY OF THE FINAL ROUGHNESS AND CUTTING FORCES DURING CUTTING OF COLD WORK TOOL STEEL

This study investigates the influence of different texturing inclinations on the cutting forces and surface roughness during hard turning with ceramic cutting tools of X100CrMoV8 cold work tool steel. Four linear textures with inclinations ranging from 0° to 45° were tested. The results show that textured tools exhibited similar cutting forces to the reference tool, with a slight increase using a 30° inclination. Surface roughness measurements indicated minor variations among the textured tools, some reducing and others increasing roughness. The texturing inclinations had limited effects on cutting forces and surface roughness in this experimental setup.

A Carbon‐Stabilized Austenitic Steel with Lower Hydrogen Embrittlement Susceptibility

High‐strength steels are susceptible to H‐induced failure, which is typically caused by the presence of diffusible H in the microstructure. The diffusivity of H in austenitic steels with face‐centered cubic (fcc) crystal structure is slow. The austenitic steels are hence preferred for applications in the hydrogen‐containing atmospheres. However, the fcc structure of austenitic steels is often stabilized by the addition of Ni, Mn, or N, which are relatively expensive alloying elements to use. Austenite can kinetically also be stabilized using C. Herein, an approach is applied to a commercial cold work tool steel, where C is used to fully stabilize the fcc phase. This results in a microstructure consisting of only austenite and M7C3 carbide. An exposure to H by cathodic hydrogen charging exhibits no significant influence on the strength and ductility of the C‐stabilized austenitic steel. While this material is only a prototype based on an existing alloy of different purposes, it shows the potential for low‐cost H‐resistant steels based on C‐stabilized austenite.

Ceramic reinforced composite coatings on cold work tool steel fabricated by wired direct energy deposited plasma

Ceramic-based coatings are beneficial in improving the microstructural and micromechanical performance of the surface exposed to extreme conditions. Due to their high melting point and exceptional hardness, ceramic-based carbides and borides are deposited on surfaces using various techniques. In this study, the 90MnCrV8 cold work tool steel surface was coated with in situ ceramic FeW, B4C, and TiB2. The process was accomplished using plasma-transferred arc (PTA) direct energy deposition technique. The coatings' microstructural (phase structure, distribution chemical composition), micro-mechanical (microhardness, indentation modulus of elasticity, creep behavior, and plasticity indices), and tribological characteristics (wear and friction behavior) were examined. No voids, cracks, or discontinuity defects were found in the produced coatings. Ceramic particle-reinforced composite coatings have superior hardness. The highest hardness was observed in TiB2 ceramic coatings. They also outperformed as-plasma-modified coatings in terms of micro-mechanical properties. The superior toughness was measured in FeW-containing coatings (highest H3/E2 ratio), and the highest creep resistance was determined in B4C and TiB2 coatings. The indentation elasticity modules increased approximately 8 times with the ceramic reinforcement. The highest indentation elasticity modulus values were observed in boron-containing coatings. Ceramic particle-reinforced composite coatings performed 5 to 9 times improved wear resistance. The lowest Coefficient of friction (COF) was observed in the B4C coating. It was observed that the chemical affinity of B4C coatings is outstanding. B4C coatings exhibited superior micro-tribo-mechanical properties to other ceramic and as-plasma-modified coatings.

DEUTSCHE EDELSTAHLWERKE CRYODUR 2721

Abstract Deutsche Edelstahlwerke Cryodur 2721 is a medium-carbon, nickel-chromium alloy cold-work tool steel. This oil hardening type cold work tool steel offers a combination of high hardness, good wear resistance, high toughness, and good machinability. This datasheet provides information on composition, physical properties, microstructure, hardness, and elasticity. It also includes information on forming and heat treating. Filing Code: TS-839. Producer or source: Deutsche Edelstahlwerke Specialty Steel.

Influence of Grooves Angle of Textured Ceramic Tools on the Final Roughness and Cutting Forces of Cold Work Tool Steel

Ceramic tools are a feasible solution for machining hard steels due to their excellent performance in high-temperature environments, which improves productivity. However, the high cutting speeds achieved with ceramic tools can generate cutting temperatures so high that they damage the surface roughness of the component. Therefore, this study aims to analyze the influence of different texturing inclinations on the final roughness of the component and the cutting forces during cutting on Al2O3 with TiC for the turning of 1.2990 cold work tool steel. The experimental setup involved testing five different texture grooves inclinations on the rake face of CNGA 120408 inserts, with a recommended cutting speed of 180 m/min, feed of 0.15 mm/rev, and a depth of cut of 0.5 mm. The tests were carried out in dry conditions. Results showed that the textured tools produced lower cutting forces (8%) and better surface roughness (improvement of 16% for Ra and 18% for Rz) than the reference tool without texture. Therefore, texturing inclinations can be used to mitigate the impact of high cutting speeds on the component during ceramic tool machining.

Sliding wear behaviour of conventional and cryotreated PM Cr-V (Vanadis 6) ledeburitic tool steel

Cryogenic treatment is a widely accepted method for extending the tool life of tool steels. This study focuses on investigating the tribological properties of PM Cr-V cold work tool steel subjected to conventional and cryogenic treatments. The aim of the study is to compare the reciprocal sliding wear performance of Cr-V cold work tool steel under different treatment conditions. The Cr-V tool steel specimens were cryotreated at temperatures of −75 °C, −140 °C, or −196 °C, followed by double tempering at 170 °C or 530 °C for 2 h. Cryotreated specimens exhibited a 10% increase in hardness compared to conventionally treated specimens after tempering at 170 °C. However, specimens cryotreated and tempered at 530 °C showed a 7% drop in hardness. Reciprocating sliding wear tests were conducted at room temperature using an Al2O3 ball as the counter-body to simulate abrasive wear. The results indicate that the friction coefficient is primarily influenced by the applied load and sliding velocity rather than the material treatment. Cryogenic treatment at 170 °C improved the wear performance by approximately 24% compared to conventionally treated specimens, while cryotreated specimens tempered at 530 °C did not exhibit any improvement in wear performance compared to conventionally treated specimens.

DEUTSCHE EDELSTAHLWERKE CRYODUR 2510

Abstract Deutsche Edelstahlwerke Cryodur 2510 is a high-carbon, manganese-chromium-tungsten-vanadium alloy cold-work tool steel. This oil hardening type cold work tool steel offers a combination of high hardness, good wear resistance, and good cutting edge retention. This datasheet provides information on composition, physical properties, microstructure, and hardness. It also includes information on heat treating. Filing Code: TS-838. Producer or source: Deutsche Edelstahlwerke Specialty Steel.

Niobium Carbide Coatings Grown on Cold Work Tool Steel AISI D3 by Thermomechanical Processing: Characterization, Wear and Corrosion Behaviors

Niobium Carbide Coatings Grown on Cold Work Tool Steel AISI D3 by Thermomechanical Processing: Characterization, Wear and Corrosion Behaviors

Innovations in Cold Work Tool Steels- Research and Development

Innovations in Cold Work Tool Steels- Research and Development

Optimization of wear-, fracture- and corrosion performance of Vanadis 6 steel through cryogenic treatment and tempering

Vanadis 6 cold work tool steel was vacuum austenitized, room temperature quenched, differently cryogenically treated (-75, -140 and -196 °C for different durations) and double tempered, at temperatures of either 170 or 530 °C. Galling resistance was assessed by pin-on-disc testing of differently treated specimens against CuSn bronze, at wide ranges of sliding velocities and loads. The obtained results show that cryogenic treatments combined with low temperature tempering improves anti-galling performance of the steel. The best tribological properties were obtained when high-temperature tempering was combined with cryogenic treatment at -196 °C, due to the maximum extent of microstructural alteration generated by this kind of treatment. The improvement in wear performance is accompanied with slight but undisputable increase in corrosion resistance of the steel, at almost no affected toughness as compared with the state after conventional heat treatment. In conclusion, the obtained results imply an opportunity to simultaneously improve wear performance, corrosion resistance and toughness of the examined steel, by choosing a proper combination of cryogenic treatment and tempering.

The behavior of cutting discs for mechanized tunneling under cyclic loading conditions

In the case of a heterogenous ground condition, tunneling tools are exposed to cyclic loading. The cyclic loads can exceed the materials' permanent load-bearing capacity, which is associated with fatigue crack growth. Subsequently, the coalescence of fatigue cracks can cause spalling of material from the tool surface, leading to the deterioration of their functionality. The problem of fatigue damage on tunneling tools has lately been recognized. However, the underlying micromechanism of subcritical crack growth and the counteraction of fatigue by advanced material concepts still require fundamental research. In this work, miniaturized cutting discs made of different tool steels are subjected to a laboratory scale fatigue test and subsequently analyzed concerning fatigue damages and the material response to cyclic loading. The hot work tool steel X40CrMoV5-1, widely used for cutting discs in industrial practice, showed fatigue crack growth and significant plastic deformation of the cutting edge under cyclic loading, leading to chip formation and spalling at the cutting edge. An improvement was found by using X153CrMoV12 ledeburitic cold work tool steel, which offers a higher strength due to the coarse chromium carbides distributed in the microstructure. Due to their high young modulus, the carbides can inhibit the plastic deformation of the softer metal matrix at the cutting edge, thus increasing the edge retention and suppressing chip formation.

Effect of heat treatments on the wear resistance of HVAF and HVOF sprayed tool steel coatings

Iron-based coatings are an attractive solution for many wear applications, considering sustainability requirements such as avoidance of critical raw materials and toxic substances. Cold worked tool steels are one potential, yet very undiscovered, material option for coating applications. As a bulk, their careful heat treatment typically produces a martensitic carbide microstructure with very good wear resistance. Compared to bulk materials, the thermal history of a thermally sprayed coating in the as sprayed state is quite different as the microstructure of the sprayed coating does not form in equilibrium. This study explored the potential of AISI D2 cold worked tool steel as a thermal spray coating under different wear conditions. The study investigated different heat treatments to achieve different microstructures of the powder and coatings and their effect on the wear and cavitation erosion properties of the HVOF and HVAF sprayed thermally sprayed tool steel coating. It is important to understand whether the properties of thermally sprayed coatings, which initially have a high defect density, can be improved by heat treatments, and how modification of the phase structures of iron-based coatings affects their properties, in order to extend the use of these coatings.

Pressure-Assisted Lubrication of DC01 Steel Sheets to Reduce Friction in Sheet-Metal-Forming Processes

Friction in sheet-metal-forming processes not only affects the values of the force parameters of the process but also determines the quality of the surface of the drawpieces. This paper presents an approach to reducing the coefficient of friction by directly applying pressurized oil to the contact zone. For this purpose, a special test stand was built to carry out the strip draw test, commonly used to model the phenomenon of friction in the deep-drawing process. This test consisted of pulling a strip between flat countersamples made of 145Cr6 cold-work tool steel covered with an abrasion-resistant Mtec (AlTiN) coating. During the pilot tests, various contact pressures, lubricants with different viscosities, and different lubricant pressures were used. The influence of friction conditions on the surface roughness of the samples and the relationship between the friction conditions and the value of the coefficient of friction were determined. The supply of the lubricant under pressure into the contact zone has a beneficial effect on reducing friction. The coefficient of friction decreases with increasing lubricant pressure for contact pressures of 2–6 MPa. For a contact pressure of 8 MPa, the lubricant pressure is the least favorable for reducing the coefficient of friction. At higher lubricant pressures (12 and 18 bar), the lubrication efficiency depends on the viscosity of the lubricant and decreases with increasing contact pressure.

Friction Behaviour of 6082-T6 Aluminium Alloy Sheets in a Strip Draw Tribological Test.

Aluminium alloy sheets cause many problems in sheet metal forming processes owing to their tendency to gall the surface of the tool. The paper presents a method for the determination of the kinematic friction coefficient of friction pairs. The determination of coefficient of friction (COF) in sheet metal forming requires specialised devices that 'simulate' friction conditions in specific areas of the formed sheet. In this article, the friction behaviour of aluminium alloy sheets was determined using the strip drawing test. The 1-mm-thick 6082 aluminium alloy sheets in T6 temper were used as test material. Different values for nominal pressures (4.38, 6.53, 8.13, 9.47, 10.63, and 11.69 MPa) and different sliding speeds (10 and 20 mm/min.) were considered. The change of friction conditions was also realised with several typical oils (hydraulic oil LHL 32, machine oil LAN 46 and engine oil SAE 5W-40 C3) commonly used in sheet metal forming operations. Friction tests were conducted at room temperature (24 °C). The main tribological mechanisms accompanying friction (adhesion, flattening, ploughing) were identified using a scanning electron microscope (SEM). The influence of the parameters of the friction process on the value of the COF was determined using artificial neural networks. The lowest value of the COF was recorded when lubricating the sheet metal surface with SAE 5W40 C3 engine oil, which is characterised as the most viscous of all tested lubricants. In dry friction conditions, a decreasing trend of the COF with increasing contact pressure was observed. In the whole range of applied contact pressures (4.38-11.69 MPa), the value of the COF during lubrication with SAE 5W40 C3 engine oil was between 0.14 and 0.17 for a sliding speed of 10 mm/min and between 0.13 and 0.16 for a sliding speed of 20 mm/min. The value of the COF during dry friction was between 0.23 and 0.28 for a sliding speed of 10 mm/min and between 0.22 and 0.26 for a sliding speed of 20 mm/min. SEM micrographs revealed that the main friction mechanism of 6082-T6 aluminium alloys sheet in contact with cold-work tool steel flattens surface asperities. The sensitivity analysis of the input parameters on the value of COF revealed that oil viscosity has the greatest impact on the value of the COF, followed by contact pressure and sliding speed.