H13 Tool Steel Research Articles

Effect of friction stir welding tool hardness on wear behaviour in friction stir welding of AA-6060 T66

Friction stir welding is a solid-state joining process with a wide range of industrial applications in the e-mobility, automotive, aerospace and energy industries. However, friction stir welding is subjected to process-specific challenges, including comparatively high process forces and friction stir welding tool wear resulting from tribological interaction between the tool and workpiece. The geometric-related friction stir welding tool wear can cause varying material flow conditions, lateral path deviations and premature tool failure, with detrimental economic and technological consequences. This study systematically analyses the wear behaviour of friction stir welding tools as a function of tool hardness. To compare and differentiate the geometric-related tool wear as a function of tool hardness, experiments were carried out with a hardness of 240 HV, 410 HV and 580 HV. Whereas 240 HV is non-hardened, 410 HV is 50% of the secondary hardness maximum and 580 HV is the secondary hardness maximum of the tools made of H13 tool steel (hot-working steel, X40CrMoV5-1). During the experimental tests, the shoulder and probe exhibited varying wear and geometrical deviations. The investigations were carried out with a force-controlled robotized welding setup in which AA-6060 T66 sheets with a thickness of 8 mm were joined by weld seams up to a total length of 80 m.

Comparison of novel TiN coated and uncoated carbide tool in CNC green machining of AISI H13 to minimize tool wear

To compare the tool wear in green machining (dry turning) of AISI H13 tool steel using novel TiN coated and uncoated carbide tools. The work material chosen for the study is AISI H13 tool steel of dimension 25 mm diameter and 50 mm length. The type of cutting tool selected for the turning operation is novel TiN coated and uncoated carbide tool. The designation of the cutting tool used is CNMG120408. Three input parameters are considered, cutting speed (m/min), feed rate (mm/rev), depth of cut (mmm) and each varied at three different levels for conducting L9 experimental study. Two groups of experimental study are selected (novel TiN coated and uncoated) with 27 samples per group. The sample size is calculated with 80 % of total pretest G power. In total, 54 samples were taken for the study of tool wear. The testing set-up of tool wear in carl zeies microscope. The experimental study was conducted in the green machining (dry turning) environment. The Average of tool wear (microns) The novel TiN coated carbide tool is lesser tool wear and uncoated carbide tool is higher tool wear are recommended. All the results obtained were analysed for its significance by SPSS software and the graphs were plotted and the level of significance was found to be 0.048 (p < 0.05). The samples machined with novel TiN coated carbide tool gives good results compared with uncoated carbide tool to minimize Tool wear.

Microstructures and Mechanical Properties of H13 Tool Steel Processed by Selective Laser Melting

Microstructures and Mechanical Properties of H13 Tool Steel Processed by Selective Laser Melting

Microstructure and Mechanical Properties of Aisi H13 Tool Steel Generated by a Laser Remelting Under Various Laser Exposition Conditions

Microstructure and Mechanical Properties of Aisi H13 Tool Steel Generated by a Laser Remelting Under Various Laser Exposition Conditions

Microstructure and Mechanical Properties of Aisi H13 Tool Steel Generated by a Laser Remelting Under Different Cooling Rates: A Comparative Analysis between Experiment and Simulation

Microstructure and Mechanical Properties of Aisi H13 Tool Steel Generated by a Laser Remelting Under Different Cooling Rates: A Comparative Analysis between Experiment and Simulation

Modelling and analysis of a customized die for blow moulding machine

This paper concentrates on the modelling of a customized bottle shape using CATIA software and analyzed for the reaction of H13 Tool steel for thermal changes occurs inside the shape of the die designed which can be used in the blow moulding machine where HDPE material is used to extract the bottle from the designed die. From the results of analysis, the total temperature and heat flux at three different temperatures could be compared by applying thermal analysis in order to known the physical properties of the model designed by also applying static analysis. One such conceptual model can be printed using 3D metal printing for further research in this area of study. Overall, by equipping designers with a library of “bottle-design” features from a CAD/CAM system, the overall period is shortened and simplified, and the same geometrical data can be passed downstream for printing.

Optimization of Process Parameter in Wire Electrical Discharge Machining of H11 Tool Steel Using Response Surface Methodology

Abstract: Conventional machining is now being superseded by non-conventional machining to cope up with increased demand of machining of complex shapes with high surface finish machining and dimensional accuracy. Wire electric discharge machining (WEDM) is electro-thermal principle based nontraditional machining, widely used for machining of electrically conductive materials. This paper summarized, the parametric influence of Pulse-on duration (Ton), Pulse-off duration (Toff) and Pulse peak current (Ip) on material removal rate (MRR), surface roughness (SR) of H11 tool steel. Response surface methodology (RSM) is used for modelling and optimization. ANOVA has been carried out to identify importance of the machining parameters on the performance characteristics considered. Further the verification experiment has been carried out to confirm the performance of optimum parameters. The results from this study will be useful for selecting appropriate set of process parameters to WEDM machining of H11 tool steel.

Numerical investigation on crack analysis of H13 fixed die and structural analysis of moving die with two different materials

Die casting is forcing molten metal into a mould with high pressure. Die casting has two dies namely moving die and fixed die where the moving one will move over the fixed die. Die casting is majorly used for high-volume production. This paper focused on the physical phenomenon of die casting for two dies (moving die and fixed die) using two different alloy materials with variable material chemical compositions. The numerical analysis is carried out for the die casting process to determine the crack formation zone by temperature distribution and structural analysis by stress-strain relationship. The numerical analysis is carried out for both the dies. The fixed die is analyzed with an H13 tool steel material with two moving die materials as aluminum alloy (A356) and magnesium alloy (AZ91D). Both the dies (fixed and moving) were designed by using design software and meshing is carried out followed by analysis using the analysis software. The physical parameter for the dies is applied that is temperature distribution is carried out by applying a temperature of 850 °C and 650 °C over the fixed die for aluminum and magnesium alloy, respectively. Structural analysis is carried out for the moving die with a load of 1,000 N for both aluminum and magnesium alloys with 1000 number of iterations. The results from the numerical analysis are derived and analyzed for both temperature distribution and structural analysis. The crack formation zone is found out by means of temperature gradient and the stress-strain relationship is found out by means of structural analysis. From the results, it was concluded that the crack zone is obtained at 1.22E-10 °C/mm and 6.856E-14 °C/mm of thermal gradient and structural analysis in terms of maximum stress of 446.94 MPa and 448.52 MPa for aluminum and magnesium alloys, respectively.

Impact of cutting fluid on hybrid manufacturing of AISI H13 tool steel

PurposeThis paper aims to analyse the effects derived from the presence of residual coolant from machining operations on the Directed Energy Deposition of AISI H13 tool steel and the quality of the resulting part.Design/methodology/approachIn the present paper, the effectiveness of various cleaning techniques, including laser vaporising and air blasting, applied to different water/oil concentrations are studied. For this purpose, single-layer and multi-layer depositions are performed. Besides, the influence of the powder adhered to the coolant residues remaining on the surface of the workpiece is analysed. In all cases, cross-sections are studied in-depth, including metallographic, microhardness, scanning electron microscopy and crack mechanism analyses.FindingsThe results show that, although no significant differences were found for low oil concentrations when remarkably high oil concentrations were used the deposited material cracked, regardless of the cleaning technique applied. The crack initiation and propagation mechanisms have been analysed, concluding that the presence of oil leads to hydrogen induced cracking.Originality/valueHigh oil concentration residues from previous machining operations in hybrid manufacturing led to hydrogen induced cracking when working with AISI H13 tool steel. The results obtained will help in defining future hybrid manufacturing processes that combine additive and subtractive operations.

Effect of process parameters for wire EDM of AISI H13 tool steel

Traditional machining processes struggle to machine materials with extremely high hardness. As a result, novel machining techniques such as ECM, USM and EDM have been developed for machining these materials. The Wire EDM process parameters of AISI H13 tool steel are optimized in this research using an effective approach. Gap Voltage, Pulse On Time, Pulse Off Time and wire feed are the input machining parameters used in the present work to achieve the highest MRR and lowest SR. The response table and response graphs were used to define the ideal levels of machining parameters. The significance of the machining parameters was decided by means of ANOVA. The greatest statistical effect on MRR is Gap Voltage (90.75%), other factors are not significant. The greatest statistical effect on SR is Gap Voltage (67.05%), followed by pulse off time (19.62). The confirmation experiments indicated that it is possible to increase the material removal rate and decrease the surface roughness by the proposed statistical technique.

Design and Testing of a WAAM Retrofit Kit for Repairing Operations on a Milling Machine

Repairing, remanufacturing, and refurbishing high value metal components are crucial to move towards a more sustainable economy. Nowadays, repairing operations on high value parts, such as dies, are generally performed using time-consuming manual approaches that rely on the operator’s expertise. The research idea of this paper is to develop a retrofit kit to provide additive capabilities to an existing milling machine, allowing automatic repairing of components thanks to a fast switch between additive and machining operations without a relevant economic investment such the acquisition of a brand-new machine: the final cost of the solution is lower than 10% with respect to the mean cost of a 5-axis milling machine. The additive technology used in this work is Wire Arc Additive Manufacturing (WAAM) that is characterized by a higher deposition rate and a simpler and cost-effective equipment with respect to other techniques (e.g., laser cladding). The design of the system is illustrated in the paper together with the analysis of the results achieved repairing a test case: a die casting mold made of AISI H13 tool steel.

Hybrid additive manufacturing of hot working tool steel H13 with dissimilar base bodies using Laser-based Powder Bed Fusion

Hybrid additive manufacturing (HAM) describes the combination of additively built structures onto a conventionally manufactured base body. The advantages of both manufacturing processes are combined in one process chain. As a result, new applications can be achieved with higher cost-effectiveness. With the Additive Manufacturing (AM) process a bonding zone is created that is comparable to a welded joint. In order to evaluate the quality and mechanical properties of the bonding zone, two steels (42CrMo4 and 25CrMo4) are investigated as base body materials with the hot working tool steel X40CrMoV5-1 (AISI H13) for the AM structure. Process parameters for Laser-based Powder Bed Fusion of X40CrMo4V5-1 are developed to achieve a crack and defect free structure as well as an optimized bonding zone in dependency of the base body material. Furthermore, the chemical and mechanical properties are examined in the as-built and heat-treated state. It is observed that a crack-free material bonding is possible and samples with relative densities above 99.5% are obtained. The size of the bonding zone depends on the material of the base body as well as post-process heat treatment. An average hardness of 600 HV1 can be achieved in the “as-built” state.

Effect of Laser Speed on Microstructure and Mechanical Properties of AISI H13 Tool Steel Prepared by Laser Powder Bed Fusion Process

Effect of Laser Speed on Microstructure and Mechanical Properties of AISI H13 Tool Steel Prepared by Laser Powder Bed Fusion Process

Improvement of Build Speed and Quality of H13 Tool Steel Processed by Laser-Beam Powder Bed Fusion with a High-Power Laser

Improvement of Build Speed and Quality of H13 Tool Steel Processed by Laser-Beam Powder Bed Fusion with a High-Power Laser

Influence of Selective Laser Melting Technology Process Parameters on Porosity and Hardness of AISI H13 Tool Steel: Statistical Approach.

The correct setting of laser beam parameters and scanning strategy for Selective Laser Melting (SLM) technology is a demanding process. Usually, numerous experimental procedures must be taken before the final strategy can be applied. The presented work deals with SLM technology and the impact of its technological parameters on the porosity and hardness of AISI H13 tool steel. In this study, we attempted to map the dependency of porosity and hardness of the tested tool steel on a broad spectrum of scanning speed—laser power combinations. Cubic samples were fabricated under parameters defined by full factorial DOE, and metallurgic specimens were prepared for measurement of the two studied quantities. The gathered data were finally analyzed, and phenomenological models were proposed. Analysis of the data revealed a minimal energy density of 100.3 J/mm was needed to obtain a dense structure with a satisfactory hardness level. Apart from this, the model may be used for approximation of non-tested combinations of input parameters.

Thermal Fatigue Model of Aluminium Alloy Die Casting H-13 Dies under Thermo-Mechanical Cycle

In industrial fields, thermal fatigue behavior has recently acquired an important role which is mainly related to the interaction between mechanical and thermal conditions. This paper proposes a thermal fatigue model of H13 tool steel under thermos-mechanical cycles. A test apparatus was used to assess the thermal fatigue resistance of materials to estimate surface crack area when specimens are subjected to thermal cycling. Thermal cycling up to 700°C was used, and crack patterns were examined after 1850, 3000, and 5000 cycles. Temperature distributions were measured at different locations in the test specimens. A model was developed to establish a relationship between mechanical cycling and thermal analysis. From the results, the thermal fatigue resistance was significantly improved over the control parameter after heating and cooling during thermomechanical cycles. The model was applied to determine the best performance and in-service life of die casting tools.

Effect of microstructure and defect formation on the bending properties of additive manufactured H13 tool steel

Due to its high strength and wear resistance and good fracture toughness at low and high temperatures, AISI H13 tool steel has been widely used to fabricate components such as injection molds, die casting dies, and hot forging tools. Components with complex geometries can be produced by additive manufacturing (AM); however, the success of this manufacture depends on the formed microstructure and mechanical properties, which are associated with the process parameters. The mechanical properties of H13 tool steel processed by AM reported in the literature are limited to those obtained through hardness and tensile tests. Thus, this study aims to correlate the bending properties of H13 tool steel with its microstructure and process parameters when processed by the Powder Bed Fusion (PBF) technique. The samples were produced with different energy densities (approximately 200, 400, and 600 J/mm³) and analyzed by XRD, OM, SEM, and ACOM-TEM. The amount of retained austenite in the cellular microstructure and the porosity decreased as the energy density increased. The sample manufactured with 400 J/mm³ presented the highest density and bending stress values. In contrast, the sample produced with 600 J/mm³ showed a smaller number of defects and more extensive deformation before fracture. This behavior was explained considering the fraction of retained austenite, intrinsic tempering, and presence of defects. The fracture mechanism comprised a mixture of cleavage and dimple formation. This study demonstrates that the bending properties of H13 tool steel processed by PBF are directly related to the resulting microstructure and process parameters used to fabricate the parts.

Fabrication of FSW Tool Pins Through Turning of H13 Tool Steel: A Comparative Analysis for Residual Stresses

In the present research, measurement of residual stress induced during turning and threading operations for the fabrication of two types of pin profiled friction stir processing/welding (FSP/FSW) tools, i.e. cylindrical profiled pin tool and cylindrical threaded profiled pin tool, is being dealt with. Workpiece was chosen to be H13 tool steel with a diameter of 22[Formula: see text]mm and 110[Formula: see text]mm length. Turning and threading was done on CNC machine tools using CNMG 12404-THM uncoated tungsten carbide cutting tool. For residual stress measurement of the workpieces, an XRD-based Pulsetec[Formula: see text]-X360n portable residual stress analyzer setup was used. The experimental results show that the cylindrical pin profile tool had a compressive residual stress of [Formula: see text][Formula: see text]MPa and compressive residual shear stress of [Formula: see text][Formula: see text]MPa, while the cylindrical threaded pin profile tool had a compressive residual stress of [Formula: see text][Formula: see text]MPa (51.8% more) and compressive residual shear stress of [Formula: see text][Formula: see text]MPa (40% less). It has been concluded that due to threading operation on the cylindrical threaded pin profile, the value of residual stress is more in it, and since the stress is compressive in nature, it would have a better positive impact while doing FSP/FSW than that of the cylindrical profiled pin tool.

Effects of laser melting+remelting on interfacial macrosegregation and resulting microstructure and microhardness of laser additive manufactured H13/IN625 bimetals

Macrosegregation at the interface in Multi-Material (MM) structures fabricated by Selective Laser Melting (SLM) has evidenced deleterious effects on interfacial bonding reliability, but its fundamental understanding is less revealed. Therefore, this work vertically prepared MM parts of H13 tool steel and IN625 superalloy by SLM, as an example, to explore the interfacial macrosegregation mechanism. According to the mechanism, a liquid layer of unmixed H13 can exist at the molten pool bottom due to the no-slip boundary condition in fluid mechanics and solidifies as an H13 macrosegregation beach. Considering the higher liquidus temperature of H13 (1483 °C) than IN625 (1300 °C), a region cooler than the H13 solidification temperature exists within the IN625 molten pool; therefore, when the melted but unmixed H13 liquid is entrained into the cooler region by fluid flows, it can solidify quickly, forming H13 macrosegregation peninsulas/islands. The laser melting+remelting strategy developed to mitigate interfacial macrosegregation reveals its significant contribution to efficient migration of H13 into IN625 molten pools in a layer-by-layer manner, forming a broad interface. As the direct reflection of interfacial macrosegregation, the microstructure experiences a cellular-columnar-cellular transition across the H13/IN625 interface. Even a peninsula with H13 microstructural features is observed in an IN625 molten pool, verifying the rapid solidification of intruded H13 in IN625. Finally, the microhardness values with varying standard deviations across the interface successfully evaluate the interfacial macrosegregation on a macro-scale. These results can provide theoretical support to mitigate interfacial macrosegregation and benefit the development of MM structures with good interfacial bonding reliability by SLM.

Pilot Demonstration of Hot Sheet Metal Forming Using 3D Printed Dies.

Since the popularization of press hardening in the early noughties, die and tooling systems have experienced considerable advances, with tool refrigeration as an important focus. However, it is still complicated to obtain homogeneous cooling and avoid hot spot issues in complex geometries. Additive Manufacturing allows designing cavities inside the material volume with little limitation in terms of channel intersection or bore entering and exit points. In this sense, this technology is a natural fit for obtaining surface-conforming cooling channels: an attractive prospect for refrigerated tools. This work describes a pilot experience in 3D-printed press hardening tools, comparing the performance of additive manufactured Maraging steel 1.2709 to conventional wrought hot work tool steel H13 on two different metrics: durability and thermal performance. For the first, wear studies were performed in a controlled pilot plant environment after 800 hot stamping strokes in an omega tool configuration. On the second, a demonstrator tool based on a commercial tool with hot spot issues, was produced by 3D printing including surface-conformal cooling channels. This tool was then used in a pilot press hardening line, in which tool temperature was analyzed and compared to an equivalent tool produced by conventional means. Results show that the Additive Manufacturing technologies can be successfully applied to the production of press hardening dies, particularly in intricate geometries where new cooling channel design strategies offer a solution for hot spots and inhomogeneous thermal loads.