High Speed Steel Research Articles

Gear Train Optimization of High Speed Machinery by using CATIA and ANSYS

This project aims to optimize gear trains for high-speed machinery using CATIA and ANSYS. Gear trains are crucial in various mechanical systems, especially in high-speed applications where efficiency and reliability are essential. The objective is to combine CATIA for designing and modelling gear trains with ANSYS for analysing their performance under high rotational speeds. Helical gear train use for Reverses Motion design as per requiment of power and motor speed. Same design check for maximium load by load on pinion taken as step of 13K, 15K, 20K, 25K and 30K Newtons are applied on helical gear and check the stress and other parameters material High speed steel. Dynamic analysis model also be carried for mode frequency Keywords: Gear trains, Finite element analysis, CATIA, ANSYS.

Preparation and performance study of highly durable silicone rubber superhydrophobic surfaces

Superhydrophobic coatings are widely applied in aerospace and other fields to address issues such as surface drag reduction, anti-icing, and corrosion resistance. Due to the poor durability and unstable performance encountered in the application of most superhydrophobic coatings, we have combined the template method with the spray method to prepare a superhydrophobic surface with excellent durability. Experimental results demonstrate that the contact angle and sliding angle of the prepared surface reached 160.9° and 2.5°, respectively. Importantly, even after undergoing tests such as high-load sandpaper abrasion, tape peeling, and high-speed steel ball impact, the surface maintained outstanding hydrophobic performance. Furthermore, the surface exhibited not only excellent chemical corrosion resistance and self-cleaning effects but also, after experiencing high-load mechanical wear, extended the ice formation delay time to 201 seconds compared to a silicone rubber surface. This study employed a simple and environmentally friendly preparation process, providing robust guidance for the theoretical analysis and practical operation of designing and preparing superhydrophobic surfaces with outstanding durability.

Residual Stress Variations in Substrate (AISI D2) during Directed Energy Deposition Process of High-Speed Tool Steel (AISI M4) Powder

This study aims to observe the residual stress in a substrate and predict stress behavior during the laser deposition process (DED) using finite element analysis (FEA). The residual stress observed on the substrate surface indicated that stress variation during the deposition process increases with proximity to the deposition area, resulting in higher residual stress levels. Additionally, tensile residual stress tends to increase with the height of the deposition area. While variations in the deposition area size influenced the residual stress, consistent stress levels were observed at the same measurement points across different area sizes. The deposition process was simulated using FEA, which confirmed that stress behavior is influenced by melting and solidification cycles. The residual stress levels after cooling aligned well with those observed in actual experiments. Therefore, this study suggests that stress variations can be effectively predicted by simulating the deposition process prior to conducting actual experiments.

Enhance the tribological performance of soft AISI 1045 steel through a CrN/W-DLC/DLC multilayer coating

Special equipment vehicles typically operate in complex environments, leading to wear and failure of the chassis's rotary seal shaft predominantly made of soft AISI 1045 steel. An effective approach to prolong the service life is to apply a hard coating on the working surface. Previous research have primarily concentrated on the coating for hard high-speed steel. However, the significant disparity in physical characteristics between soft AISI 1045 steel and the hard coating results in a weak interface adhesion. This study produces a CrN/W-DLC/DLC multilayer coating on the soft AISI 1045 steel with strong interfacial adhesion and superior friction and wear property through modulation of the CrN transition layer thickness. The multilayer coating consists of five layers, a CrN transition layer, a Cr layer, a Cr/WC alternating layer, a W-DLC/DLC alternating layer, and the topmost DLC layer. The thickest CrN interlayer coating achieves the Lc2 and Lc3 value of 13.9 ± 0.2 N and 20.4 ± 0.9 N. The optimized CrN/W-DLC/DLC coating reduces the internal stress of the DLC coating and enhances its adhesion. Importantly, the average friction coefficient and wear cross-sectional area of the CrN/W-DLC/DLC multilayer coatings decrease accordingly. The thickest CrN interlayer coating exhibits superior outstanding wear resistance evidenced by an average friction coefficient of 0.119, a steady-state friction coefficient of 0.097 and a wear volume of 1.508 × 106 μm3. The presence of a high proportion of sp2 bonds in the thickest CrN interlayer coating, which are susceptible to graphitization, along with a thicker transition layer that enhances the coating's support, leads to narrower wear traces. The primary wear mechanisms observed in the friction and wear test of CrN/W-DLC/DLC coatings are oxidative wear and tribo-abrasive wear. The work provides a significant promise for application in vehicle rotary seal components and a theoretical reference for enhancing the wear resistance of the seal surface.

Strain Cyclic Characteristics and Ratchetting Behaviors of High-Speed Railway Train Axle Steel EA4T

Strain Cyclic Characteristics and Ratchetting Behaviors of High-Speed Railway Train Axle Steel EA4T

Characteristic analysis of high-speed steel powder prepared by gas atomisation

The performance of high-speed steel (HSS) powder is a prerequisite for the preparation of high-performance powder metallurgy HSS. The physical properties, microstructure, and solidification characteristics of HSS powder prepared by nitrogen gas atomisation were systematically studied and analysed in detail. For the atomised TPM558 HSS powder, the morphology is spherical and the particle size distribution is wide. The smooth small particles of satellite powder attach to the surface of large particles. Shrinkage pits caused by solidification shrinkage exist on the surface of large particles. The average cooling rate is between 104 and 106 K·s−1, with the increase of cooling rate, the powder surface tends to be smooth, and the grain structure is transformed in the order of cellular to dendritic to radial. The single powder particle surface shows fine-equiaxed grains, while the internal presents columnar grains. The crystalline phases of the powder are austenite, ferrite, martensite, and carbide, and the carbide includes MC carbide with face-centred structure and M2C carbide with hexagonal structure. The average nano-hardness of the powder is 9.93 GPa, resulting in poor formability, and it can be pressed and formed only after adding binder.

Fundamental investigation on the time-variance of process stability

AbstractDisturbance factors, such as self-excited tool vibrations, limit the performance of modern machining processes and thus restrict the quality, productivity and sustainability of industrially manufactured components. The dynamic process stability is subjected to significant variances especially at the beginning of the tool life. To precisely quantify these variances, series of milling tests were conducted and analyzed using tools made of high speed steel (HSS) and cemented carbide for the machining of EN AW-7075. In all test series, a critical initial decrease of the stability limit was detected directly at the beginning of the tool life. In the following, a significant increase and subsequent almost constant stability limit was observed. In the case of the HSS cutters the achieved stability limit exceeded the initial level substantially. An increase in the process forces and flank wear was also measured over tool life but the progression cannot directly explain the extend and characteristics regarding the stability limit. The findings described have a considerable impact on the appropriate design of manufacturing processes and experiments to determine the dynamic stability of cutting operations.

The oil lubricated fretting wear behavior under different sliding displacements and frequencies of Ti6Al4V titanium alloy as affected by micro-shot peening

The fretting wear behavior under oil lubricants is of great practical significance since oil is usually used to regulate fretting regime for minimizing wear. In this study, micro-shot peening (MSP) was performed on Ti6Al4V titanium alloy, in which 0.6 MPa injection air pressure, 60 s shot time and high-speed steel particles with an average diameter of 50 μm were used. Surface topography, microstructure, hardness and compression residual stress of test samples were examined. Oil lubricated fretting wear tests were then conducted between titanium alloy sample and GCr15 counterbody under different sliding displacements and frequencies. The test results show that the surface structure of MSP treated samples experienced severe plastic deformation, the surface hardness was increased from 310.8 HV to 433.5 HV, and a compression residual stress of −303.5 MPa was introduced within surface layer. Moreover, MSP treatment reduced the coefficients of friction through producing a micro-dimpled surface. Thereby, the fretting wear resistance of MSP treated sample under oil lubricated condition was improved. By comparison, at higher sliding displacement and frequency, the ability of MSP treatment to resist fretting wear was improved more significantly since more better lubricating effect can be obtained. Fretting damage of untreated sample under oil lubrication was mainly attributed to fatigue wear, delamination wear, abrasive wear and oxidation wear, while that of MSP treated sample was mainly regional peeling off and abrasive wear.

Impact of Laser Shock Peening Without Ablative Coating Process on the Surface Characteristics and Wear Behavior of High-Speed Steel

Impact of Laser Shock Peening Without Ablative Coating Process on the Surface Characteristics and Wear Behavior of High-Speed Steel

Study on Microstructure, Mechanical Properties, Tribological Properties and Service Performance of CrAlN and CrAlBN Coatings Deposited on Powder Metallurgy High-Speed Steel (PM-HSS) and Shaper Cutter by Arc Ion Plating Technique

CrAlN and CrAlBN coatings were prepared on the surface of high-speed steel and shaper cutter by physical vapor deposition (PVD) technique using arc ion source. In the process of coating preparation, the adhesive layers were deposited by low bias voltage (−40 V) and the working layers are deposited by high bias voltage (−130 V). The effects of the addition of B element on the microstructure, hardness, elastic modulus and wear resistance of CrAlBN coating were studied. The results show that B element and its compounds exist in amorphous form in the coating, resulting in lattice distortion of the coating, increase of coating hardness to 37.1 GPa, and decrease of elastic modulus to 406.2 GPa. The addition of B element increases the uniformity of the columnar structure distribution and decreases the width of the columnar structure and grain size. The resistance to elastic deformation and plastic deformation of CrAlBN coating is improved, the wear resistance is improved. The performance of CrAlN and CrAlBN coatings on shaper cutter was studied. It was found that the main failure mode of shaper cutters is boundary wear and the wear mechanism of coatings had changed obviously. CrAlBN coating is mainly due to fatigue induced failure, accompanied by some diffusion wear. The addition of B element makes the CrAlBN coating have excellent resistance to oxidative wear, abrasive wear and diffusion wear during cutting. The results show that the addition of B element can improve the microstructure and mechanical properties of CrAlN coating, and the preparation of CrAlBN coating on the surface of the shaper cutter can significantly improve the service life of the coated shaper cutter, which has significance for the development of the shaper cutter industry.

Synthesis and characterization of titanium-titanium nitride deposition on SS-CRM 487/1 high speed tool steel

ABSTRACT The present study uses DC magnetron sputtering for synthesis of a TiN and Ti-TiN bilayer on the surface of SS-CRM 487/1 high-speed tool steel. This coating is deposited on the substrate at 400°C. The deposited substrate is characterised by different experimental techniques. The scanning-electron microscopy (SEM) is used for film morphology, cross-sectional examination, and worn-out surfaces. The profilometer is used for measuring the film thickness and roughness. However, the nano-indentation is used to extract the intrinsic hardness and young’s modulus evaluation. The ball on-disc sliding test under dry conditions is employed for tribological properties of deposited high-speed tool steels. The test results indicate the improvement in the wear resistance for the Ti-TiN bilayer except four bilayers as no of layer increases.

Characteristics and Formation Mechanism of Oxide–Sulfide Complex Inclusions in High-Speed Railway Wheel Steel

Characteristics and Formation Mechanism of Oxide–Sulfide Complex Inclusions in High-Speed Railway Wheel Steel

Machinability studies of Al–4Mg/in-situ MgAl2O4 nano composites: measurement of cutting forces and machined surface roughness

The present research aims to study the dry turning machinability characteristics of in situ Al-4Mg/MgAl2O4 nanocomposite by High-Speed Steel tool. The influence of various machining process parameters, such as feed rate, depth of cut and cutting speed on the surface roughness and cutting force of the nanocomposites was measured while performing dry turning. From the turning operation results, it is noticed that up to 100 m min−1, the cutting force increased and with further increases in cutting speed, the cutting force starts decreasing up to 150 m min−1. The type of chips and built-up edge (BUE) development were studied using a scanning electron microscope. BUE formations were higher at low cutting speeds (50 m min−1) and lower at high cutting speeds (150 m min−1). At a given depth of cut and feed rate, with an increase in cutting speed, the length of the chip and chip curls increased. Further, higher 2 wt% of in situ MgAl2O4 addition changes long-curled chips to segmental-type chips. With a feed rate of 0.14 mm/rev, the Al-4Mg/1 wt% MgAl2O4 nanocomposite showed the lowest surface roughness value of 2.4 μm proving usage of high speed steel can provide a better surface finish while turning Al-4Mg/MgAl2O4 nanocomposite.

Structure and Properties of High-Speed Steel Surfaised Layer Irradiated by Pulsed Electron Beam

Structure and Properties of High-Speed Steel Surfaised Layer Irradiated by Pulsed Electron Beam

Ssessment of cutting fluids supplying method influence on contact processes when drilling stainless steel 12Х18Н10Т

The authors have considered the process of blind holes processing during drilling operations when processing stainless steel 12Х18Н10Т. Spiral drills made of high-speed steel were used as cutting tools. There are some typical problems in this process such as difficulty of removing chips and cutting fluids supply to the machining zone. One more problem is that while removing chips along spiral grooves, they rub against the surface of the hole and thus become deformed, which results in the deterioration of surface quality. Therefore, a comparative assessment of various coolants influence was carried out depending on the method of their supply under closed cutting conditions.

Enhancing the Cooling Efficiency of Aluminum-Filled Epoxy Resin Rapid Tool by Changing Inner Surface Roughness of Cooling Channels.

In low-pressure wax injection molding, cooling time refers to the period during which the molten plastic inside the mold solidifies and cools down to a temperature where it can be safely ejected without deformation. However, cooling efficiency for the mass production of injection-molded wax patterns is crucial. This work aims to investigate the impact of varying surface roughness on the inner walls of the cooling channel on the cooling efficiency of an aluminum-filled epoxy resin rapid tool. It was found that the cooling time for the injection-molded products can be determined by the surface roughness according to the proposed prediction equation. Employing fiber laser processing on high-speed steel rods allows for the creation of microstructures with different surface roughness levels. Results demonstrate a clear link between the surface roughness of cooling channel walls and cooling time for molded wax patterns. Employing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm for low-pressure wax injection molding can save time, with a cooling efficiency improvement of approximately 34%. Utilizing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm on the inner walls of the cooling channel can save the cooling time by up to approximately 60%. These findings underscore the significant role of cooling channel surface roughness in optimizing injection molding processes for enhanced efficiency.

Microstructure and antibacterial properties of AlCrTiZrWN high-entropy alloy nitride synthesized using HiPIMS under various N2/Ar flow ratios

This paper reports on the use of high-power impulse magnetron sputtering (HiPIMS) to deposit (AlCrTiZrW)Nx high-entropy alloy (HEA) nitride films to a thickness of 1 μm on SKH-9 high-speed steel, SUS304 stainless-steel, and Si wafers. The primary aim was to elucidate the effects of N2/Ar flow ratio (from 10/100–150/100 sccm) on the structure of the resulting materials and antibacterial properties. Co-sputtering was performed using multiple simultaneous targets to overcome the difficulties in manufacturing HEA targets at industrial scales. XRD analysis revealed a FCC structure with (111) orientation under nitrogen gas flow of 70 sccm. Increasing the nitrogen flow to 90 sccm shifted the preferred orientation to the (200) direction. The highest water contact angle (113°) and highest hardness value (27.6 GPa) were achieved under a nitrogen flow of 70 sccm, while the best Rp value (22.7 × 105 Ω‧cm2) was achieved under 110 sccm. The antibacterial performance of the coated samples exceeded that of uncoated SUS304 stainless-steel. Overall, the incorporation of nitrogen had positive effects on HEA film properties.

Effect of nano-SiC on microstructure evolution and enhanced high wear resistance mechanism of laser surface alloyed M42 high-speed steel

M42 high-speed steel is one of the main materials for preparing bimetallic band saw parts. In this paper, nano-SiC particles of different densities (0–1.00 mg/mm2) were precoated on the surface of M42 high-speed steel samples, then, the samples were prepared by laser alloying. The matching relationship between the quantity, size, and type of martensite and MxCy carbides in laser alloyed samples play a decisive role in improving wear resistance. It is found that under the optimized particle density of 0.75 mg/mm2, compared with M42 high-speed steel, the hardness was increased by 50%, the wear rate decreased by 84.7%. The matching relationship between Martensite and MxCy carbides formed by laser alloying of nano-SiC particles on the improvement of wear resistance was elucidated.

Simulation and Optimization of Surface Roughness and Process Performance during Machining of HSS by Micro-WEDM Technology.

When machining high-speed steels (HSS) with micro-wire electrical discharge machining (micro-WEDM), high surface quality is achieved as standard. The value of the roughness parameter Ra is less than 0.2 μm. However, the problem is the performance of the electroerosion process (MRR), which is low. This problem is related to the mechanical and physical properties of the HSS in combination with the setting of the main technological parameters (MTP). The proposed solution to eliminate this problem relies on the selection of proper procedures for the determination of optimization criteria in relation to Ra and MTP, with the inclusion of properties of the machined material. The solution consisted in the identification of four significant physical (ρ, κ) and mechanical (Rm, HRC) indicators of HSS properties, on the basis of which a suitable combination of the process output parameters Ra and MRR can be determined through established mathematical regression models using simulation and optimization. In the next step, the proper values of the MTP output process parameter settings, which correspond to the optimized output parameters Ra and MRR during machining of HSS by micro-WEDM technology, were then obtained by the same approach.

Effect of Tempering on Structure and Properties of Plasma Surfacing of R2M9U High-Speed Tool Steel

Effect of Tempering on Structure and Properties of Plasma Surfacing of R2M9U High-Speed Tool Steel