High Speed Steel Surface Research Articles

ECM-YOLO: a real-time detection method of steel surface defects based on multiscale convolution

Steel surface defects, characterized by multiple types, varied scales, and overlapping occurrences, directly impact the quality, performance, and reliability of industrial products. Proposing a high-precision and high-speed steel surface defect detection algorithm is crucial for ensuring product quality. In this regard, this paper introduces ECM-YOLO, a detection network based on YOLOv8n. First, addressing the insufficient information capture of the C2f module, the C2f enhanced multiscale convolution processing (C2f_EMSCP) module is proposed, enhancing global and local feature capture capabilities through multiscale convolutions. Second, to further enhance the network’s robustness and focus on critical information, the channel prior convolutional attention (CPCA) mechanism is integrated between the backbone and neck networks to facilitate more efficient information transmission. Last, a novel, to the best of our knowledge, detection head, i.e., multiscale simple and efficient anchor matching head (MultiSEAMHead), is proposed to mitigate accuracy issues arising from overlaps between different types of defects. Experimental results demonstrate that ECM-YOLO achieves mAPs of 78.9% and 68.2% on the NEU-DET and GC 10-DET data sets, respectively, outperforming YOLOv8n by 2.5% and 4.4%. Moreover, ECM-YOLO excels in model parameters, computational efficiency, and inference speed compared with other models. These findings highlight the applicability of ECM-YOLO for real-time defect detection in industrial settings.

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.

Tribological properties of high-speed steel surface with texture and vertical fibers

Inadequate lubrication of the two touching surfaces during friction can lead to severe wear, especially in metal cutting. Therefore, a surface with synergistic anti-friction effect of texture and solid lubricant was proposed to improve lubrication. A mesh texture with excellent wettability was prepared on the high-speed steel (HSS) surface by laser, and then nylon fibers were vertically implanted into the grooves of the texture using the electrostatic flocking technology. The friction and wear state of different surfaces (smooth, textured, flocking) under dry/oil-lubricated were studied by a linear reciprocating wear tester. The coefficient of friction (COF) under different working conditions was used to analyze the anti-friction properties, and the wear rate was used to evaluate the wear resistance of the surface. The results showed that the tribological properties of flocking surfaces were better than those of the other two surfaces. This is because the addition of nylon fibers eases shear at the edges of the texture. The broken fibers form a solid lubricating film on the specimen surface, which prevents the surface from being scratched by debris. In addition, it is found that COF decreases with increasing load. Finally, the rapid wettability of the oil droplets on the flocking surface shows the great potential of the surface for lubrication and anti-friction.

Effect of high-speed steel surface nitriding treatment on adhesion and wear resistance properties of nitrogen-doped diamond-like carbon coatings

Based on the principle of hollow cathode, diamond-like carbon (DLC) coatings were deposited on high-speed steel by plasma enhanced chemical vapor deposition (PECVD). The mechanism of the experimental parameters on the adhesion and wear behavior of the multilayer coatings, prepared by plasma nitriding substrate and DLC N-doping, were systematically investigated via Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), micro-Vickers tester, friction and wear tester analysis. It was found that the deposition speed and structure of DLC coatings can be efficiently improved by different contents of N doping. With the increase of nitrogen content, the content of sp3 bond in DLC coating first increased to 60.82 % and then decreased to 58.73 %. Meanwhile, the friction coefficient of DLC coating first decreased and then increased. Combined with plasma nitriding treatment for substrate, the wear resistance of DLC coating was effectively improved by optimizing the hardness gradient between the coating and the substrate. Under the same friction conditions, the wear rate was reduced by about 50 %, while the adhesion of DLC coating was improved from HF4 to HF1 in comparison with non-nitriding and non-N-doping DLC coatings. It was revealed by the mechanistic-based model that the resistance by nitriding layers played a more important role than an increase in coatings thickness due to the reasonable hardness gradient in resisting deformation. Based on the N-doped DLC + DLC structure, the surface hardness of the coating gradually increased to 1970.9 HV. The hard outer layer provided sufficient load-carrying capacity and wear resistance during the friction process, thus decreasing the generation of wear debris and the depletion of coating.

Effect of deep cooling times on the architecture and performance of DLC coating system

At present, the research on deep cooling times mainly focuses on the influence of a certain material. The research on the deep cooling treatment process of the coating composite system focuses on the insulation time, deep cooling temperature, and cooling rate, and there are few studies on the influence of deep cooling times on the coating composite system. This paper preliminarily explored the influence of the cryogenic treatment process changing cryogenic times on the structure and properties of the diamond-like carbon film (DLC) coating on an M35 high-speed steel surface under the condition of a certain total holding time. When two cryogenic treatments were carried out at -140°C and -196°C, the content of the SP3 hybrid bond decreased. The bonding force of DLC coating is improved after several cryogenic treatments, but the wear resistance of DLC coating decreases with the further increase of cryogenic times. This process has certain reference significance for improving the bonding force and wear resistance of DLC coating.

Status and Perspective of High-Energy Beam Surface Strengthening: High-Speed Steel.

High-speed steel (HSS) is primarily used to manufacture cutting tools and roll materials for various machine tools. Improving the hardness, wear resistance, and corrosion resistance of HSS is of great significance to the development of the manufacturing and tool industries. The high-energy beams, consisting of laser, plasma beam, and electron beam processing (e.g., surface remelting, cladding, and alloying), have the advantageous characteristics of high heat source energy and good surface processing effect. The research status and perspective of the above three processing techniques on the surface properties (in particular, hardness, wear resistance, and corrosion resistance) of HSS is reviewed, and the principles, advantages, and disadvantages of the three strengthening methods are discussed. High-energy beam surface alloying appears to be the most cost-effective of HSS surface strengthening methods and is promising to receive increasing research attentions in the future.

Wettability enhancement of high-speed steel surface with electrostatic flocking method

Due to the important role of cutting fluid in lubrication of tools, achieving its better wetting effect on the surface has become a research hotspot. Castor oil is widely used in machining with excellent lubrication, but its poor wettability cannot be ignored. To enhance the wettability of castor oil on the tool surface, grooves were prepared on the surface of high-speed steel (HSS) by laser, then nylon fibers were vertically implanted into the grooves by electrostatic flocking. The optimization experiments of groove sizes, electrostatic voltage and fiber length were performed, then flocking surfaces with enhanced wettability were evaluated through the self-propulsion, and high-temperature wetting tests. The results show that the penetration length of oil in the flocking grooves (5.71 mm) is 2.28 times that of the non-flocking grooves (1.74 mm). Moreover, the dense fibers increase the heat exchange area at a high temperature, resulting in a rapid rise in temperature of droplet. Thereby the viscosity resistance of the oil is reduced, accelerating the penetration of oil droplets, which are completely wetting for only 0.3 s at 80 °C. This study is of reference value and practical significance for the application of flocking surfaces enhancing the wettability of cutting fluid.

Temporal synchronization framework of machine-vision cameras for high-speed steel surface inspection systems

Temporal synchronization framework of machine-vision cameras for high-speed steel surface inspection systems

Tribological properties of ion-modified composite coatings

The paper presents the results of a study of one of the ways to increase the wear resistance of “duplex” coatings applied to cutting tools, which are due to preliminary diffusion saturation of the tool surface with nitrogen (known as ion nitriding) followed by physical deposition of a hard coating (Ti, Cr) N. The proposed coating also contains an additional layer with an impurity of ions, deposited on a preliminary nitrided surface of high speed steel before the deposition of a hard coating. Tests were carried out to evaluate the effect of these modified layers on the tool life of the HSS tool. The greatest wear resistance after "triplex" - treatment was achieved during ion implantation of titanium into a pre-nitrided surface. The coefficient of friction of the modified layer was studied at different contact temperatures. Ionic mixing contributes to the appearance of a thin surface layer with an amorphous-like structure, which prolongs the stage of normal wear, which significantly increases the tool life as a result of the self-organization process.

Microstructure and properties of WC/diamond/Co-based gradient composite coatings on high-speed steel fabricated by laser cladding

Improving the wear resistance and corrosion resistance of high-speed steel (HSS), WC/diamond/Co-based gradient composite coatings were produced on HSS substrates by laser cladding with different composition powder mixture (Co-Cr alloy powder, 80Co-Cr alloy powder+20WC, 53Co-Cr alloy powder+40WC+7diamond, wt%). The macromorphology, microstructures, and phase composition were characterized by optical microscope (OM), scanning electron microscopy (SEM) equipped with energy-dispersive spectrometry (EDS), and X-ray diffraction (XRD) techniques. The microhardness, wear resistance, and corrosion resistance of the gradient coatings were also investigated, respectively. The results indicate that the prepared WC/diamond/Co-based gradient composite cladding layer has a fine morphology on the cross sections and a gradient transition of the grain size has been achieved. The microhardness result presents gradient distribution along the depth of the coating. The microhardness is strengthened due to the dispersions of M7C3 (M is Fe, Cr), Co3C, CrCo, Cr3C2, and Fe3C in the composite coating, and the highest microhardness of 1342 HV0.2 can be detected in the cladding layer. The friction coefficient values of the coatings range from 0.27 to 0.40, which is much lower than that of the substrate (0.50–0.60). Furthermore, the wear loss of coatings (1.1 mg) decreases by more than 3 times comparing with that of the substrate (3.5 mg). The polarization resistance results show that the cladding layer has excellent corrosion resistance with polarization resistance that can reach the value of 236488.1 Ω·cm2. The gradient transition of the mechanical properties and chemical metallurgical combination between particle (WC, diamond) and adhesive phase can be obtained in laser cladding, which improves the wear resistance and corrosion resistance of the HSS surface.

Mechanical and high-temperature tribological properties of CrAlN/TiSiN multilayer coating deposited by PVD

Hard nitride coatings have the prospect of acting as protective layers for cutting tools because of their excellent mechanical properties and wear resistance. To enhance the mechanical, tribological, and high-temperature oxidation properties, the structural design of the coating is important. In this study, TiSiN, CrAlN/TiSiN bilayer and CrAlN/TiSiN multilayer coatings were deposited on the surface of high-speed steel by multi-arc ion plating technology. The microstructure, phase composition, mechanical properties and high-temperature tribological properties of prepared coatings were analyzed. Results indicated that the TiSiN and CrAlN/TiSiN bilayer coatings contain TiN phases and the CrAlN/TiSiN multilayer coating contains three main phases of TiN, AlN and CrN. The CrAlN/TiSiN multilayer coating possesses a denser microstructure than the other two coatings. The multilayer structure improves the cohesive and bonding strength of the coating by reducing the shear stress. The CrAlN/TiSiN multilayer coating exhibits a stable coefficient of friction and excellent wear resistance during high-temperature friction. The formation of TiO2 and Al2O3 oxide layers on the surface of the coating in a high-temperature environment contributes to the desired tribological properties of the coatings.

Microscopic Images and Microstructure of High-Speed Steel Surface after Gas-Laser Cutting

Microscopic Images and Microstructure of High-Speed Steel Surface after Gas-Laser Cutting

Composite coatings for cutting tools after ion mixing

Ways of increasing the wear resistance of "duplex" coatings applied to cutting tools due to preliminary diffusion saturation of the tool surface with nitrogen followed by physical deposition of a hard coating (Ti, Cr)N are proposed. The proposed coating, in addition to the above, contains an additional modified layer with an impurity of ions (metals: Ti, Zr, W and Al in combination with three non-metals N, C, and O), applied to a prenitrided surface of high-speed steel before the deposition of a hard coating. The highest wear resistance after "triplex"-treatment was achieved by ion implantation of titanium into a prenitrided surface. The coefficient of friction of the modified layer is studied at different contact temperatures. An improved ability of a layer with an ionic mixture to accumulate elastic deformation energy is shown. Ionic mixing contributes to the appearance of a thin surface layer with an amorphous-like structure, which prolongs the stage of normal wear, significantly increasing the tool life as a result of the self-organization process.

Effect of plasma beam irradiation on the microstructure and phase composition of high-speed steel R6M5

Abstract The present study is devoted to research into the morphology and structural-phase state of an R6M5 high speed steel surface layer after it was affected by a plasma beam. It was discovered, that R6M5 steel is a multi-phase material with an α-phase, γ-phase (retained austenite) and carbide phase just as in the initial state. The main phase component of the R6M5 steel matrix before and after plasma beam processing was an α-phase (γ → α’-martensite): lamellar and lath martensite; but lamellar martensite is dominated by a volume ratio ~90 % gross share α’-martensite. The γ-phase as the second morphological component of the steel matrix (retained austenite) yields within the martensite plates the form of twintype colonies with a volume ratio of ~6 %. It was established that there were М6С -type carbide particles of complex composition (Fe,W,Mo)6C in the material just as in the initial state. It should be said that in its initial state, the dislocation structure, formed under the effect of the plasma beam, is characterized by fairly high value of excess density of dislocations with an average value of ρ± = 2.0 × 1010 cm-2 (in the initial state ρ± = 1.7 × 1010 cm-2) along with scalar density. The depth of torsion curve of the face-centered space lattice in the α’-martensite is χ = 500 cm-1 (in the initial state it is equal to χ ~436 cm-1), the amplitude of the inner long-distance voltage is σ∂ = 280 МPа (in the initial state it is equal to σ∂ = 260 МPа). Thus, the amplitude of shift voltage is equal to σL = 420 МPа (in the initial state it is σL = 350 МPа); nevertheless, σL > σ∂ remains the mean torsion-curve of the fcs-lattice of α’-martensite maintaining its lamellar nature after the effect of the electron beam much as in the initial state.

Effect of plasma beam irradiation on the microstructure and phase composition of high-speed steel R6M5

Abstract The present study is devoted to research into the morphology and structural-phase state of an R6M5 high speed steel surface layer after it was affected by a plasma beam. It was discovered, that R6M5 steel is a multi-phase material with an α-phase, γ-phase (retained austenite) and carbide phase just as in the initial state. The main phase component of the R6M5 steel matrix before and after plasma beam processing was an α-phase (γ → α’-martensite): lamellar and lath martensite; but lamellar martensite is dominated by a volume ratio ~90 % gross share α’-martensite. The γ-phase as the second morphological component of the steel matrix (retained austenite) yields within the martensite plates the form of twintype colonies with a volume ratio of ~6 %. It was established that there were М6С -type carbide particles of complex composition (Fe,W,Mo)6C in the material just as in the initial state. It should be said that in its initial state, the dislocation structure, formed under the effect of the plasma beam, is characterized by fairly high value of excess density of dislocations with an average value of ρ± = 2.0 × 1010 cm-2 (in the initial state ρ± = 1.7 × 1010 cm-2) along with scalar density. The depth of torsion curve of the face-centered space lattice in the α’-martensite is χ = 500 cm-1 (in the initial state it is equal to χ ~436 cm-1), the amplitude of the inner long-distance voltage is σ∂ = 280 МPа (in the initial state it is equal to σ∂ = 260 МPа). Thus, the amplitude of shift voltage is equal to σL = 420 МPа (in the initial state it is σL = 350 МPа); nevertheless, σL > σ∂ remains the mean torsion-curve of the fcs-lattice of α’-martensite maintaining its lamellar nature after the effect of the electron beam much as in the initial state.

Tribological Behavior of Co-WC Composite Coatings

A novel Co-WC composite coating was deposited on the surface of high speed steel (HSS) substrate by an energy-efficient method of electrodeposition. The effects of process parameters on friction and wear properties of the composite coatings were evaluated, and the worn morphologies of Co-WC composite coatings were investigated by scanning electron microscopy. Results revealed that the incorporation of WC particles can significantly improve the wear resistance of the coating. As the current density was increased to 6.5Adm-2 and the WC concentration was increased to 35g/L, the Co-WC composite coating had the lowest friction coefficient and wear loss.

The effect of phase on microstructure and mechanical performance in TiAlN and TiSiN films

To study the effect of phase on the microstructure and mechanical properties of nitride coatings, three films of TiN, TiAlN, and TiSiN were prepared on the surface of high-speed steel using hollow cathode assisted multi-arc ion plating technique. The XRD lines of the three films were analyzed and calculated by linear analysis. The element and phase of the film were observed and analyzed by x-ray Diffraction (XRD), Transmission Electron Microscope (TEM), energy dispersive x-ray analysis (EDS). The microstructure and film thickness of the coating were characterized by scanning electron microscopy (SEM). The surface roughness of the film was observed by Confocal laser scanning microscope (CLSM). The hardness, friction coefficient, and coating/substrate adhesion of the film were tested by the G200 nanometer hardness tester and CETR UNMT-1 surface micro-nano mechanical test system. We discovered two different reinforcement mechanisms. The high microscopic strain value (1.309 × 10−3) in the TiAlN film was related to the formation of Ti3AlN substitutional solid solution in the film formed a large lattice distortion,however, the coating/substrate adhesion (33.5 N) was lowered. The result of independent nucleation and growth of the Si3N4 phase in the TiSiN film refines the structure of the film, alleviating the increase of microscopic strain. At this time, the coating/substrate adhesion reaches the highest value of 40 N and the film surface roughness reaches the minimum value of 0.451 μm. The results also show that the TiSiN coating can obtain good coating/substrate adhesion without pre-plating.

Effects of Topography and Modified Layer by Plasma-Shot Treatment on High-Speed Steel

In this study, plasma shot (PS) treatment was applied to high-speed steel (HSS) surfaces using a titanium carbide electrode to confirm the effect of discharge current (Ip) on the formation of a single dimple and analyze a modified layer. The roughness of modified surfaces increased when Ip increased, and energy-dispersive X-ray spectrometry showed an increase in titanium atom density when Ip and electrode consumption volume (Ve) increased. A friction test confirmed that the modified surface’s friction was reduced by discharge dimples under low-load conditions. Vickers hardness test confirmed that the hardness of the modified surface was ~ 300–600 HV higher than that of an untreated HSS surface. Moreover, it increased with an increase in Ip. However, application of PS treatment to the edge of surfaces on the workpiece caused shape deterioration. The deterioration size of the edge of the modified layer increased when Ip increased. To solve this issue, we propose a novel method named position-adjusted PS (PA-PS) treatment. PA-PS treatment is used to adjust the end of the electrode in the order of tens of micrometers from the edge of the workpiece to avoid the deterioration of the edge form. Under Ip = 21 A, PA-PS formed a modified layer without deteriorating the edge shape of the workpiece, thus confirming the PS characteristics applied to HSS surfaces. Moreover, PA-PS treatment solved the shape deterioration of the edge on modified surfaces via PS treatment.

Characteristics of Diamond-Like Carbon Coating Using Plasma Assisted Chemical Vapor Deposition on Steel Tool

High Speed Steel (HSS) tool is commonly used in engineering applications, especially as cutters. The shortfall of this materials are wear and corrosion. However, these can be reduced by coating the surface of the material. Therefore, the purpose of this research is to investigate the effects of Diamond Like Carbon (DLC) coating, quenching heating treatment, and tempering on the physical and mechanical properties of HSS surface. The physical characteristics which will be investigated is the micro structure, while the mechanical characteristics are hardness, wear and corrosion rate. HSS has variations in their chemical composition (% mass): 0.75–1.5 C, Co >12, V > 5, 4–4.5 Cr,10–20 W and Mo. Furthermore, DLC coating uses Plasma Assisted Chemical Vapor Deposition (PACVD) technique with variation in the duration of coating (1,2,3,4,5 and 6 hours) at temperature of 300℃, with pressure variations of 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0 millibar. DLC coating material be treated from methane or ethane gas, which is streamed into the fire with Argon (Ar). The result shows variations in DLC coating and the hardness grade depends on the coating time and pressure variation. DLC coating for a duration of 4 hours under 1.8 mbar pressure can reduce the surface hardness of HSS tool by 62% accompanied by increased ductility.

On the roughness of the gas-laser cut surface of high-speed steel

On the roughness of the gas-laser cut surface of high-speed steel