440C Stainless Steel Research Articles

Wear and friction behavior of wrinkled-Ti3C2Tx /epoxy composites

Herein, the tribological behavior of the epoxy/wrinkled-Ti3C2Tx MXene composites against 440C stainless steel under dry sliding conditions was investigated. Due to the inherent brittleness and poor wear resistance of epoxy resin, wrinkled-Ti3C2Tx MXenes (delaminated using MTHPA: methyl tetrahydrophthalic anhydride) were incorporated in various concentrations (0.1-1 Wt.%). The sliding experiments showed little impact of MXenes’ addition on the friction coefficient values. Meanwhile, the wear resistance of epoxy was significantly improved, particularly with 0.2 wt% MXene, showing a 91.82% improvement. This improvement of the epoxy’s wear properties at a low MXene concentration is attributed to the homogenous MXene distribution and strong interfacial adhesion. The present study opens up new horizons for the application of epoxy/wrinkled-Ti3C2Tx MXene nanocomposites as dry sliding wear components.

Microstructural characterization of AISI 440C stainless tool steel fabricated by laser powder bed fusion

Abstract The microstructure of a stainless tool steel AISI 440C fabricated by laser powder bed fusion (L-PBF) without pre-heating of the build plate was characterized by multi-scale experimental methods. In combination with thermodynamic calculations, the solidification and cooling-down procedures were analyzed with the intention to understand the cracking behavior of high carbon tool steels processed by L-PBF. The results showed a fully austenitic structure in the as-built sample with sub-micro cellular structures and nano-sized carbides decorating the cell walls. Significant segregation exists merely at the intersection of cell walls while it is absent along high angle grain boundaries. Factors contributing to crack-free AISI 440C are discussed, providing guidelines for future L-PBF fabrication of high-carbon tool steels.

Preparation of Ti–MoS2 coating and gradient structure via mechanical ball milling to improve the wear resistance of AISI 440C stainless steel bearing balls

Owing to its excellent wear resistance and high hardness, 440C stainless steel is widely used in the manufacturing of bearing steel balls. However, in high-speed and heavy-duty environments, bearing steel balls are prone to wear and failure, which affect their service life. This study focused on 440C stainless steel bearing balls and developed a method for preparing Ti–MoS2 coatings and nano gradient structures on the surface of the steel balls via mechanical ball milling so as to improve their wear resistance. A detailed experimental study regarding the surface microstructure and friction performance of the processed balls was simultaneously conducted. The results demonstrated that the surface of the treated bearing steel ball formed a nano gradient structure and a 4 μm Ti–MoS2 coating. The surface roughness of the treated sample decreased by 9.2% and the surface microhardness (831.9 ± 6.4 HV) increased by 28.93% compared to that of the untreated sample. The friction and wear experiments demonstrated that under a load of 80 N, the wear of the treated bearing steel balls decreased by 51.23% compared to that of the untreated bearing steel balls (9.94 ± 0.41) × 106 μm3. Our findings indicate that preparing Ti–MoS2 coatings and nano gradient structures on the surface of steel balls via mechanical ball milling is an effective approach to improving the friction performance of bearing steel balls.

Microstructural evolution of multilayered AISI 316L-440C steel composites manufactured by laser powder bed fusion

This study presents a systematic study of multilayered steel-steel composites prepared via laser powder bed fusion (L-PBF) in an open-architecture additive manufacturing system equipped with a multiple powder delivery module. Stainless steel AISI 316L powder and high‑carbon stainless steel 440C powder were chosen as the model material system. The printed samples were characterized using optical microscopy, X-ray diffraction, electron backscattered diffraction, energy-dispersive X-ray spectroscopy, X-ray tomography, and micro-hardness to understand the complex manufacturing process and its influence on the microstructure and properties. The evolution of the multilayered structure was assessed, revealing that significantly more pronounced remelting occurs when the 440C powder is deposited on the 316L band, generating a thick 440C/316L transition region and a thin 440C band. Cracks were observed primarily at the transition regions, and were attributed to a “hot cracking” mechanism. The cracks were associated with significant chemical segregation along the grain boundaries at these regions, which exhibit intrinsically higher hot cracking susceptibility than the single-material bands. This was particularly prevalent for mixtures with <50 wt% SS440C (balance AISI 316L), as corroborated by thermodynamic calculations and observed crack locations. The processing-microstructure relationship was discussed in terms of the formation of defects at the transition regions. Challenges associated with crack removal in multi-material systems were discussed and guidelines for manufacturing multi-material, multilayered composites via L-PBF were provided.

Tribological Study of Fe–Cr Alloys for Mechanical Refinement in a Corn Stover Biomass Environment

The tribological behavior of three Fe–Cr alloys with Cr contents ranging from ~12 to 16 wt.% as well as low-alloy high-carbon 52100 steel were investigated using pin-on-disk wear testing. Wear tests were performed in both open atmospheric (dry) and biomass environments (wet). Delamination and abrasion were observed to be the dominant wear regimes following dry wear tests. For wet testing, adhesion and pitting corrosion were determined to be the primary wear mechanisms in the Fe–Cr alloys while adhesion and delamination/cracking were identified as the primary wear mechanisms in the 52100 steel. The 440C stainless steel and 52100 steel specimens exhibited the lowest wear volume following dry (7.58 ± 0.52 mm3 and 0.78 ± 0.05 mm3, respectively) and wet wear testing (0.11 ± 0.06 mm3 and 0.12 ± 0.09 mm3, respectively); however, these specimens exhibited the most significant corrosion damage. The 410 stainless steel specimen exhibited the best resistance to corrosion after wear testing in the deacetylated and disc-refined corn stover slurry and had measured wear volumes after dry and wet wear testing of 6.84 ± 0.88 mm3 and 0.33 ± 0.12 mm3, respectively. The worst wear resistance was observed by the 420 stainless steel specimen after both dry and wet wear testing.

Investigation of Surface Integrity of Conical Hole in Laser Polishing 440C Stainless Steel

In the machining process of 440C stainless steel using ball-end milling, the generation of machined traces is an inevitable outcome. Traditional polishing methods, when applied to the milling surfaces of small conical holes, exhibit significant limitations. However, the application of nanosecond pulsed laser polishing while maintaining dimensional integrity has proven effective in mitigating these issues. The parameters for the laser and scanning strategy were empirically determined through planar experiments. The results showed a reduction in surface roughness to a minimum value, representing a decrease of approximately 41.7%. Further validation experiments were conducted on the ball-milled surface of small conical holes. The rate of roughness reduction in these experiments surpassed that of planar surface polishing with an improvement of approximately 73.6%. The scanning strategy’s applicability was confirmed, and the post-polishing surface morphology was found to be largely in line with the prediction. The remelt layer and heat-affected zone resulting from nanosecond laser polishing were observed to be below 5 μm, significantly preserving the dimensional integrity of the conical hole’s internal surface. Moreover, nanosecond laser polishing was found to substantially enhance the surface hardness of the material, with an increase ranging from 100% to 180%. This study underscores the efficacy of nanosecond laser polishing in enhancing the internal surface of small conical holes, thereby improving the surface properties. Consequently, this method presents a reliable solution for the removal of machined traces from complex internal surfaces.

Analysis the Influence of Pressure Distribution on Exhaust Manifold Using FEM

Abstract: In this paper the 3D model of the exhaust manifold was realized using Autodesk Inventor Professional 2024 and finite element analysis was performed, in order to determine the state of stress and deformation, by applying restrictions and loads conditions. The materials chosen, for exhaust manifold, was in accordance with the specialized literature. The materials taken for static analysis was Stainless Steel 440C and Iron Gray Cast. Following the comparative study for the two models, it can be specified that the importance of the material for the construction of the exhaust manifold depends on the mass properties and their design

Interface construction of micro/nano hierarchical structure to enhance the tribological performance of carbon fabric/phenolic composite

Carbon fabric (CF)/polymer composites are potential lubricating materials, which could be used for plane bearing lining, sliding guide rails, and other moving parts of advanced equipment. But the low bonding strength at the interface between the carbon fibers and the polymer matrix is a great challenge to developing high-performance CF/polymer composites. In this study, the CF is coated with an active transition layer using high-adhesion polydopamine (PDA) as an ideal plate for the TiO2 micro/nano hierarchical structure to construct CF-PDA-TiO2. This hierarchical structure is made of micro-bundles, each composed of numerous nanorods, and decorated on CF surface densely and uniformly. The interfacial combination of CF-PDA-TiO2 and phenolic resin (PF) shows excellent performance, and the interlaminar shear strength (ILSS) of CF-PDA-TiO2/PF is improved from 10.48 MPa to 37.22 MPa, attributed to the improved interfacial physicochemical interaction. Furthermore, the tribological performance of CF-PDA-TiO2/PF with size of Φ30 mm✕5 mm is characterized by sliding against 440C stainless steel ball with diameter of 8 mm using ball-on-disc sliding wear tester (MPX-3). The tribological results demonstrate that the friction coefficient and wear rate of CF-PDA-TiO2/PF are reduced by 37.91% and 77.6%, compared to CF/PF. Moreover, the CF-PDA-TiO2/PF maintains low friction coefficient and wear rate under high-load and high-speed sliding conditions. This is mainly because TiO2 nanorod bundles exhibit micro/nano multi-scale interfacial enhancement, promoting stress distribution and micro-cracks deflection etc. Moreover, TiO2 nanorod bundles could promote the formation of a uniform transfer film to decrease friction and wear. This work implies that interface construction of micro/nano hierarchical structure is a promising way to enhance the tribological performance of CF/polymer composites.

Evaluation of cryogenic cooling in CNC machining of martensitic stainless steel AISI 440C

Materials that is difficult to machine, such as AISI 440C stainless steel, show great wear on the cutting edge of inserts, which is enhanced by the heat of abrasive friction. In this study, a methodology was developed to verify the efficiency of the cutting cooling method against insert flank wear and integrity of the machined surface. In the dry cutting method, no liquid or gaseous coolant was used. Emulsifying liquid cutting fluid was applied by the continuous flow method, with the jet directed in the cutting region by the upper part of the insert. To measure the wear on the flank of the insert, a digital macroscopy method was applied. The analyzes showed that the dry cooling method presented lower machined surface roughness for 15 min (Ra = 1.449 μm). The liquid nitrogen cryogenic cooling method offered less flank wear for 15 min of machining (Vb = 0.168 mm). The machining tests showed that the TNMG160404 Class 6525 insert supports the machining parameters, for and cooling methods and the material adopted according to ABNT NBR ISO 3685 standard.

An Experimental Investigation on Machining of Hardened AISI 440C Stainless Steel Using Abrasive Water Jet Machining Process

An Experimental Investigation on Machining of Hardened AISI 440C Stainless Steel Using Abrasive Water Jet Machining Process

Investigating the effect of fused deposition modelling on the tribology of PETG thermoplastic

A widely recognized consequence of the additive manufacturing process is the deterioration of mechanical properties through the development of macrodefects, microdefects, and chemical changes. This has particularly negative impacts on fatigue and wear resistance of components produced by additive manufacturing, which limits the utility of the technology for engineering applications. In this investigation, we find that glycol-modified polyethylene terepthalate processed via Fused Deposition Modelling (FDM) exhibits a significantly lower wear rate as compared to virgin material when subjected to slow-speed dry sliding contact, which is a rare case of an additively-manufactured material with improved bulk properties. Using pin-on-disk testing, we demonstrate favorable wear resistance for additively-manufactured pins against a surface ground 440c stainless steel counterface, which reflects potential utility of the material in light-duty, low-maintenance linear and rotary motion applications. The wear behavior observed under these test conditions corresponds to an order of magnitude decrease in wear relative to existing literature. Annealing the samples results in a further decrease in wear rate, while samples produced in a dry nitrogen atmosphere exhibit increased wear and a change in morphology and thickness of the transfer film. X-ray photoelectron spectroscopy testing validates that FDM printing results in material oxidation, that this oxidation corresponds with an improvement in wear performance, and that printing in a dry nitrogen environment inhibits this change.

Estimation of Fatigue Limit and Strength Degradation Mechanism of a High Strength Steel in Petrol Environment by Means of a Small Sized Specimen with Radial Notch

Strength of structural materials used in corrosive environment will be lowered compared with that of materials used in air due to the effect of corrosion fatigue. In the previous study, fatigue tests on a type 440C stainless steel, which has been used as a part of automobile fuel injection system, in air and petrol environment were conducted by means of a small sized smooth specimen and a fatigue testing machine for the specimen performable in corrosion and flammable liquid under push-pull loading at high frequency region. However, it was difficult to investigate the effect of corrosion due to the difference of fracture morphology. In this study, fatigue tests on the same material were conducted by means of a small sized specimen with notch for matched fracture origin in air and deteriorated petrol under the same test condition. The fracture on fatigue tests with notched specimens initiated from specimen surface regardless of the test environment. In petrol that contains methanol, fatigue fracture was caused on lower stress level because minor intergranular cracks were originated by the effect of corrosion. Fatigue lives of flat specimen were correlated using the size of the inclusions and they were correlated with high accuracy. Fatigue limit was also estimated. It was confirmed that fracture origin was changed to the surface due to immersion to petrol that contains methanol. The relationship with the stress state in notch part and fatigue failure mechanism was discussed in detail.

Microstructural and mechanical properties of AISI 440C stainless steel fabricated using selective laser melting

AISI 440C stainless steel (SS440C) has excellent mechanical properties. However, its industrial application is limited because SS440C cannot be fabricated into different shapes due to its high hardness and low workability. Selective laser melting (SLM) is the most suitable method to increase the workability of SS440C because the SLM process has few restrictions on manufacturing geometry. In order to observe changes in internal porosity according to process conditions, specimens under 36 different process conditions were fabricated by SLM. The changes in microstructure and defect generation mechanism in specimens fabricated under high-density process conditions were analyzed. Phase change and mechanical properties of SS440C were studied under defect free process conditions and compared with those observed by researchers in the past.

Effects of interlayer bias voltage on the mechanical properties of tetrahedral amorphous carbon films

Tetrahedral amorphous carbon (ta-C) films with bias-regulated (namely from −50 V to −200 V) Ti interlayers were prepared on AISI 440C stainless steel substrates, followed by systematic investigation on the microstructure, mechanical, and adhesion properties of such films. In addition, molecular dynamics simulation has been employed to study the formation of Ti films deposited with different incident energy, which was found to be influenced by the bias voltage significantly. The experimental results demonstrated that varying bias voltage on the Ti interlayer exerted minor influence on the sp3C fraction and mechanical properties of ta-C films. Molecular dynamics simulations showed further support for the experimental results. The Ti interlayer exhibited the amorphous-like microstructure, and increasing Ti-atom incident energy resulted in increasing Ti/Fe interlayer thickness and a firstly rising and then descending Fe/Ti interfacial bonding strength. The adhesive failure mode can be divided into buckling crack and interfacial spallation, which was primarily attributed to the tensile-to-compressive transformation of the Ti-interlayer internal stress. Optimised adhesion property of ta-C films can be achieved with a Ti-interlayer bias voltage of ∼ -100 V.

Tribological Properties of Cu–25Zn–5Al–3Fe–3Mn Alloy at High Temperatures

Abstract High-strength Cu–25Zn–5Al–3Fe–3Mn brass has broad applications as a wear-resistant copper alloy, while its tribological behavior at high temperatures has not yet been well investigated. In this paper, the tribological behavior of Cu–25Zn–5Al–3Fe–3Mn alloy was investigated at room temperature –500 °C coupled with AISI 316L and AISI 440C stainless steel. The effects of test temperatures and counterparts on its tribological properties were systemically discussed. The results indicate that the friction and wear behavior are largely dependent on the test temperatures and counterparts. And there exists a clear distinction in the friction and wear behavior when the alloy sliding against different counterparts at RT–500 °C. The tribological properties of the alloy depend on the counterparts at RT–200 °C due to that the main wear mechanism is abrasive wear for Cu/316L pairs and plastic deformation for Cu/440C pairs. When the test temperature exceeds 300 °C, the adhesive wear is main wear mechanism. The softening resistance and oxidation process is decisive for the high temperatures tribological behavior.

Effect of Natural Surface Defects on Flaking Failure of 13Cr-2Ni-2Mo and SUS 440C Stainless Steel Ball Bearings

The sectional observations of 13Cr-2Ni-2Mo and SUS 440C stainless steel ball bearings were done. Two features were found from the observations: parabolic-shaped cracks generated the flaking failure of 13Cr-2Ni-2Mo stainless steel bearing; jellyfish-shaped wear affected the flaking failure of SUS 440C stainless steel bearing.

Tough and wear-resistant carbon fiber reinforced TiC-based composite prepared by alloyed melt infiltration at low temperatures

To improve the toughness and friction properties of carbon fiber reinforced ceramic matrix composite, a Cu alloy modified carbon fiber reinforced TiC based ceramic matrix composite was designed and prepared by TiCu alloy melt infiltration at low temperatures up to 1100 °C. The as-produced composite was mainly composed of carbon, TiC, Ti 3 Cu 4 , TiCu 4 and Cu phases. Due to the ductile Cu alloy introduced into the matrix, the composite showed good mechanical performance especially the fracture toughness. The flexural strength reached about 248.36 MPa while the fracture toughness was up to 15.78 MPa·m 1/2 . The high toughness of the composite was mainly attributed to the fiber bridging, fiber pull-out, interface debonding, crack propagation and deflection. The tribological performance of the as-produced composite was measured using SiC and 440C stainless steel balls as counterparts, respectively. The as-prepared composite exhibited good wear resistance and the wear mechanism was discussed based on the microstructural observations.

Influence of high temperature sodium exposure on microstructure and material properties of AISI 440C Stainless Steel

Influence of high temperature sodium exposure on microstructure and material properties of AISI 440C Stainless Steel

Influence of high temperature sodium exposure on microstructure and material properties of AISI 440C stainless steel

Influence of high temperature sodium exposure on microstructure and material properties of AISI 440C stainless steel

Corrosion Protection of Injection Molded Porous 440C Stainless Steel by Electroplated Zinc Coating

Zinc electroplating was used to enhance corrosion resistance of porous metal injection molded 440C stainless steel. Controlled porosity was achieved by the powder space holder technique and by using sodium chloride as a space holder material. The internal pore structure of porous 440C was deposited by zinc using electroplating with three different electrolytes of zinc acetate, zinc sulfate, and zinc chloride. Our results show that all zinc depositions on porous 440C samples significantly improved corrosion resistance. The lowest corrosion was observed with zinc acetate at 30 wt.% porosity. The developed zinc coated porous 440C samples have potential in applications in corrosive environments.