Decrease In Wear Rate Research Articles

On the formation of Ti2AlN MAX phase coatings and improvement in tool life by superimposing on tungsten carbide cutting tool for machining Ti-6Al-4V alloys

This paper presents the development of (002) textured Ti2AlN coated wear resistant tool utilizing reactive magnetron co - sputtering. The Ti2AlN coating was developed in two different Argon, Nitrogen ratios such as 64:3 and 64:4, the influence of these parameters was identified using crystallographic, microstructural, mechanical and tribological studies. Experimental studies were performed to compare the cutting force as well as the tool life of superimposed Ti2AlN tool with a commercial tool by turning titanium alloy (Ti-6Al-4V). Results from the experimental analysis revealed an 80–85 % increase in hardness, a 13–20 % decrease in wear rate and a 27 % increase in tool life for Ti2AlN coated cutting tool. According to chip morphology, there is a 12 % increase in shear angle, 43 % and 51 % decrease in friction angle and coefficient of friction respectively. The nanomechanical studies were performed which show a maximum hardness of 29.12 ± 5.4 GPa and minimum wear rate of 10.078 × 10−9 mm3/mN.m−1 for superimposed Ti2AlN.

Study on Friction and Wear Properties of Copper-Impregnated Carbon Slide Plate Under Different Humidity Conditions

The pantograph–catenary system is one of the most commonly used power-receiving modes of metro trains. Its friction and wear performances are related to the safety and stability of train operation. In this study, a copper-impregnated carbon slide plate material, widely used in numerous metro lines in China, is considered as the research object. The problem of abnormal wear of slide plates caused by the decrease in relative humidity in the autumn and winter in tunnels is studied. Current-carrying friction and wear tests under humidity conditions of 20%, 30%, and 40% relative humidity (RH) are performed to reveal the mechanism of seasonal abnormal wear of slide plates and provide a reference for the service of pantograph slide plates under low-humidity conditions. The results reveal that relative humidity significantly influences the wear process of slide plates; further, the wear rate decrease with an increase in relative humidity. As observed by laser scanning confocal microscopy, with an increase in the relative humidity, the mechanical wear of the slide surface is weakened, arc erosion is enhanced, and surface roughness is increased. The Raman spectral scan showed that with the increasing humidity, the graphitization of the surface material decreased significantly, and the molecular structure changed greatly. Scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS) analysis reveal that under high humidity conditions, a relatively complete oxide film forms on the slide plate and plays a role in lubrication and protection.

Wear behavior of GNPs/ZrO2 reinforced composite ceramics sliding against Inconel 718

Graphene/ZrO2 hybrid reinforced Al2O3/Ti(C, N) matrix composites were considered as potential cutting tool materials applied for high-speed turning of Inconel 718. The impact of GNPs/ZrO2 content and test parameters on the tribological performance of composite ceramics and wear mechanisms was investigated by the sliding wear tests against Inconel 718 using the pin-on-disk method. Results showed that GNPs contributed to the decrease in friction coefficient (COF) and wear rate concurrently. The wear rate of the ceramic incorporating 0.4 wt% GNPs and 1 wt% ZrO2 was decreased by 85.4% compared with that of the Al2O3/Ti(C, N) ceramic, showing the best wear resistance. The addition of GNPs and ZrO2 helps reduce adhesive wear and enhance mechanical properties especially fracture toughness, which is contributed to the formation of continuous and uniform protective tribo-films. In addition, appropriate increase of load and sliding speed is beneficial to improve the tribological performance of ceramics.

Development of a Ti30Hf20Nb20Ta10V10Mo7W3 refractory high entropy alloy with excellent mechanical properties and wear resistance

Refractory high entropy alloys (RHEAs) have attracted a great deal of attention for the competitive properties at elevated temperatures, whereas the ambient-temperature brittleness has been still a bottleneck for practical applications. Herein, we report on a newly-designed Ti30Hf20Nb20Ta10V10Mo7W3 RHEA which exhibits an excellent combination of mechanical properties and wear resistance in a wide temperature range. The present RHEA possesses a yield strength of 1225 ± 17 MPa together with a fracture strain of > 45 % at room temperature, showing an excellent strength-ductility synergy. The alloy also maintains considerable yield strength and ductility at elevated temperatures, outperforming numerous ductile RHEAs. In addition, the coefficient of friction and wear rate decrease with increasing temperature from room temperature to 800 ℃. Interestingly, the alloy exhibits a wear rate as low as (5.50 ± 0.11) × 10−6 mm3 N−1 m−1 at 800 ℃, which is related to the formation of continues and dense oxide layer.

Gaussian and circular oscillating laser directed energy deposition of WC/NiCu composites

In the realm of laser directed energy deposition (L-DED), the standard procedure typically using a Gaussian laser as the primary energy source. However, this well-established technique also has limitations as it generates considerable temperature gradients and residual stresses throughout the manufacturing process, resulting in notable deformation and cracking. To overcome these limitations, this study advocates for the replacement of the Gaussian laser with a circular oscillating laser. NiCu alloys and 16 wt% WC/NiCu composites were manufactured using the Gaussian laser and the circular oscillating laser deposition equipment. The results of this study reveal that the circular oscillating laser methodology exerts a pronounced agitation effect on the melt pool, thus hindering the formation of columnar dendrites and promoting the emergence of more nucleation sites for the growth of equiaxed dendrites. This method effectively refines the grains by reducing the temperature gradient of the melt pool and increasing the cooling rate. The average grain size of NiCu alloy manufactured using the circular oscillating laser is reduced by 19.5% compared to that manufactured using the Gaussian laser. The high temperature generated by laser and melt pool caused partial decomposition of WC into W and C, leading to the formation of W2C hard phases between the dendrites. Additionally, the unmelted WC particles were uniformly dispersed throughout the composites, which hindered the growth of columnar dendrites and refined the grains. Compared to the composites manufactured using the Gaussian laser, the composites manufactured using the circular oscillating laser exhibit an average microhardness increase of 15% and 11.1%, and a 76.5% and 22.2% decrease in wear rate, respectively. Composites containing 16 wt% WC manufactured using the Gaussian laser exhibit the best corrosion resistance.

The effect of recycled zinc powder content on the properties of novel novolac matrix hybrid composites

In this study, effect of recycled zinc powder reinforcement ratios and ball milling time on novolac matrix hybrid composites were investigated. The ball milling time of 2 h showed a positive effect on the hardness of the composites up to 100 HRM. Thermal analysis results showed that the increasing zinc reinforcement ratio was increased thermal stability of the composite powders. The assessment of wear resistance was conducted using a block-on-ring tribometer, and the results demonstrated that the incorporation of zinc particles significantly decreased wear rates. Additionally, 2 h ball milling times showed superior wear resistance. Specimens with 20 wt% Zn reinforcement and subjected to 2 h ball milling time exhibited approximately 93% less wear loss than Zn-free specimens.

Assessment of tribological behaviour of laser textured brake disc/composite brake pad system using adaptive neuro fuzzy interference system technique

This paper examines the impact of Laser Surface Texturing (LST) on the tribological performance of a commercial automotive brake system consisting of a metallic brake disc and composite brake pads. The study focuses on achieving an optimal combination of wear and friction, aligning with the goals of green technology. The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) methodology is used to rank the characteristics, while the Adaptive Neuro Fuzzy Interference System (ANFIS) methodology is employed to model the friction and wear behavior of the brake pad-disc system under varying normal loads and sliding speeds. At a normal load of 100 N and a sliding speed of 0.73 m s−1 under dry conditions, the brake system exhibited a minimum coefficient of friction of 0.2066 and a specific wear rate of 7.93 × 10−6 mm3 N−1-m−1. Although, there was no specific correlation found between frictional power and specific wear rate, a higher load of 100 N and sliding speed of 2.71 m s−1 resulted in decrease in specific wear rate by 83% when compared to that of untextured brake discs. By applying brake oil to the laser-textured boundary, the coefficient of friction experienced a 31% reduction.

Investigations on the temperature-dependent tribological behaviour of spark plasma sintered CNT-304 SS self-lubricating nanocomposites

ABSTRACT Herein, we report the tribological behaviour of CNT-304 stainless steel composites at room (28°C) and high temperatures (200°C). Nanocomposites of various CNT concentrations, namely 0.2, 0.5, 1.0, 2.0, 3.0, and 4.0 wt%, were prepared. A significant amount of grain refinement resulted in an increase in CNT loading. A tribological study was carried out at 28°C and 200°C. Wear resistance was found to enhance with an increase in CNT concentration at both temperatures. However, a slightly higher wear rate was observed at 200°C for the samples with CNT content < 3 wt% than their corresponding low-temperature values. About 86%, 91% drop-in wear rate was seen in 2.0 wt% CNT-304 SS, and 4.0 wt% CNT-304SS, respectively, as compared to pure SS at 28°C, which is 54% and 88% decrease at 200°C and is very promising. The decrease in wear volume with CNT content at both temperatures can be ascribed to the self-lubricating and reinforcing nature of CNTs in the metal matrix composites. Severe abrasive wear in the pristine SS samples was slowly changed to mild abrasive and lubricated wear in composites. A systematic study on the tribological behaviour of CNT-SS composites can shed light on the benefits and detriments of using them for various applications. Highlights Incorporation of CNTs into 304 SS matrix caused grain refinement. Wear rate decreased with CNT content and 4.0 wt% CNT-SS showed minimum wear rate while pristine gave the maximum at both 28°C and 200°C. About 86% and 54% decrease in wear rate were observed for 2.0 wt% CNT-304 SS at 28°C and 200°C respectively as compared to the pristine 304 SS sample. Wear rate at 200°C was slightly more than that of room temperature (28°C) for CNT content < 3 wt%. The 3.0 wt% CNT-304 SS and 4.0 wt% CNT-304 SS showed nearly the same wear rate at both ambient and 200°C test.

Tribological performance of polyamide 6/wax blend for rolling bearing, bushing and gear applications

Today, machine manufacturing is developing rapidly and plastic materials are preferred in some parts of these machines. Rolling bearings, gears, bushings and rollers are some of the machine elements manufactured from plastic in recent years. The working life of the aforementioned machine elements actually depends on the working conditions as well as the material. At the same time, the speed and load carrying capacity of the machine elements or counter materials during operation determine the life of the plastic material. In this experimental study, polyamide 6 polymer, which is among the engineering plastics used in rolling bearings, gears, rollers and bushings, was used. In addition, PA6 polymer blends with 6% wax solid lubricant were produced to increase wear resistance and their tribological performances were investigated. The polyamide 6/wax blend was first produced in granule form in twin screw extruder by compound production method. Then, test specimens were injection molded using the granules. AISI 316L stainless steel was used as a counter-disc in tribology tests. The tests were carried out under dry sliding conditions and at room temperature. Wear tests were carried out on a pin-disc wear tester at two different loads (50 N and 100 N) and four different sliding speeds (0.5, 1.0, 1.5 and 2.0 m/s). The coefficient of friction and specific wear rate of the materials were determined. According to the test results, an increase in the coefficient of friction and specific wear rate of both PA6 polymer and PA6/6% wax blend was observed with increasing sliding speed. At the load and speed ranges studied, the coefficient of friction of pure PA6 polymer varied between 0.25 and 0.36, while the coefficient of friction of PA6/6% wax blend varied between 0.10 and 0.13. The wear rate of PA6 polymer was obtained in the range of 1.2-12x10-4 mm3/Nm, while the wear rate of PA6/6% wax blend was obtained in the range of 1.2-3.0x10-5 mm3/Nm. The addition of 6% wax to PA6 polymer caused a significant decrease in both friction coefficient and wear rate and contact surface temperature.

Effect of homologous molecular crosslinking on the tribological properties of PTFE composites

AbstractA method of improving the tribological properties of hexagonal boron nitride/short carbon fibers/polytetrafluoroethylene (h‐BN/SCFs/PTFE) composites by adding homologous micropowder (MP1100) with polar groups is proposed in this study. Composites of h‐BN/SCFs/PTFE with MP1100 at 0, 8, 16, 24, and 32 wt% were prepared. The pin‐on‐disc device was used to evaluate the friction properties of composites, and wear mechanisms against duplex stainless steel was examined. The experimental results show that MP1100 micropowder improves composite mechanical properties, friction coefficient, and wear resistance of composites. A 78.4% drop in wear rate was measured for 24 wt% MP1100. Such decrease in wear rate is explained based on changes in composite molecular structure, a transfer film formed by the absorption of debris, and the formation of chemically reacted polar group compounds on the steel disc.

Effect of Laser Remelting of Fe-Based Thermally Sprayed Coating on AZ91 Magnesium Alloy on Its Structural and Tribological Properties

An Fe-based coating was thermally sprayed onto the surface of AZ91 magnesium alloy via the High-Velocity-Oxygen-Fuel (HVOF) method. The thermally sprayed coating with a thickness of 530 ± 25 µm and a porosity of 0.7 ± 0.1% did not show any macrostructural defects and did not cause any degradation of the AZ91 alloy. Laser remelting of the surface layer of the sprayed coating resulted in the recrystallization of the structure and the disappearance of presented pores, splat boundaries, and other defects. This led to an increase in the hardness of the remelted layer from the original 535 ± 20 HV0.3 up to 625 ± 5 HV0.3. However, during the laser remelting at a laser power of 1000 W, stress cracking in the coating occurred. The tribological properties were evaluated by the ball-on-plate method under dry conditions. Compared to the uncoated AZ91 magnesium alloy, a higher value of friction coefficient (COF) was measured for the as-sprayed coating. However, there was a decrease in wear rate and weight loss. The remelting of the surface layer of the as-sprayed coating led to a further decrease in the wear rate and weight loss. Based on the obtained data, it has been shown that the application of laser-remelted thermally sprayed Fe-based coatings on AZ91 Mg alloy improves hardness and tribological properties compared to bare Mg alloy and as-sprayed Fe-based coatings.

Tribological behaviors of Ta-10W alloy at elevated temperature

Ta-10W alloy has great potential in the aerospace and nuclear industries due to its good formability, high melting point and excellent high-temperature strength. The purpose of this study was to experimentally research the tribological behaviors of Ta-10W at elevated temperatures and the effects of temperatures on the friction coefficient and the wear rate of Ta-10W in sliding wear. It was found that the main wear mechanism of the material at 100°C was abrasive wear, as well as adhesive wear and slight oxidative wear occurred at 200°C and 300°C. The friction coefficients increased as the temperature rose, which was attributed to the increase in metal viscosity at elevated temperatures. The wear rate gradually decreased with the temperature rising, such that there was a conversion from severe wear to light wear. At 200°C and 300°C, a large amount of stable oxide film covered the scar surface, resulting in decreased wear rate.

Evaluation of physical, mechanical and sliding wear properties of in-situ AB-TiC composite: a comparison with NAB alloy

The purpose of the present study is to evaluate the physical, mechanical and sliding wear properties/response of cast in-situ aluminium bronze (AB)-TiC [(Cu10Al3Fe)5TiC] composite and compare with cast nickel aluminium bronze (NAB) [Cu10Al5Ni5Fe] alloy. Sliding wear tests were conducted in dry and partially lubricant conditions using a pin-on-disc machine. A test material in the form of pin was evaluated against a rotating heat-treated EN-31 steel disc. Wear loss, frictional heating and friction coefficient properties were examined. The NAB alloy showed higher tensile strength (32.7%), compressive strength (7.68% at room temperature. and 4.18% at 500 °C), hardness (8.78%) and density (3.17%), whereas thermal conductivity of the AB-TiC composite was found 4.89% higher than NAB alloy. In dry sliding condition, composite outperformed NAB alloy in terms of wear resistance up to a critical applied load and/or sliding speed. Beyond this point, the wear behavior altered. Increasing sliding speed caused to reduce wear transition load. While friction coefficient showed mixed trend. Under lubricated wear test conditions, AB-TiC composite displayed considerably higher wear resistance (50.08%, 44.41% & 51.55%) and friction coefficient (26.37%, 40.75% & 14.96%) than the NAB alloy when tested in only oil, oil with 100 μm graphite and oil with 7–10 μm graphite respectively. Arrival of seizure in general caused significantly higher wear loss and temperature rise. In addition, it caused large adhesion of the specimen material to the disc surface. The reported wear behaviour of the samples has been validated using the features of wear surfaces and subsurface regions. The latter also permitted to comprehend the working wear processes. The analysis significantly shows good impacts of the oil lubrication (with and without solid particles) in terms of decreasing wear rate, frictional heating, and friction coefficient. Formation of steady lubricating film/layer was reported to be responsible for the better wear performance of the samples. Furthermore, irrespective of material composition and microstructure there exists a precise set of test parameters (e.g. load and speed) leading to optimal wear performance wherein the beneficial impacts of load bearing capability, thermal stability of various phases predominates.

STUDY THE EFFECTS OF THE MULTINITE COAT OF THE HIGH SPEED STEEL DRILL BIT IN DRILLING

Drilling is an important metal manufacturing processes. Drill bits are used in drilling to create holes. Wear of drill bits can have an adverse effect on the quality of the drilling hole. To increase the wear resistance of drill bits, surface modifications have been introduced and studied their effectiveness. Multinite coating is a candidate for surface modification techniques to increase wear resistance of the drill bits. In this study, the effect of multinite coating on the wear resistance of drill bits has been investigated. Two types of 6 mm diameters drill bits, the uncoated high speed steel, and the multinite coated high speed steel drill bits, were used to create the hole with 30 mm in depth on ASTM A36 steel. The drilling parameters were 1,100 rpm of rotation speed and 135 mm/min of the feed rate. The thrust force and the cutting torque during drilling were measured by a force sensor. Flank wear on the drill bits were measured by overlap image technique. Also, the roughness of hole surfaces were investigated. Results showed that the higher surface hardness of multinite coated high speed steel drill bit led to a lower flank wear rate at the beginning of drilling. Consequently, built-up of chip on the multinite coated high speed steel drill bit was less compared to the uncoated one. We conclude that the higher surface hardness of multinite coated high speed steel drill bit improves the wear resistance of drill bit by a decrease of wear rate at the beginning of drilling and a lesser amount of chip built-up on the cutting edge and the surface quality of hole after drilling.

Microstructural, Mechanical, and Tribological Performances of Composites Prepared via Melt Compounding of Polyamide 6, Basalt Fibers, and Styrene-Ethylene-Butylene-Styrene Copolymer.

Basalt fibers (BFs) are environmentally friendly materials characterized by high strength and good wear resistance, and thus are popular candidates for reinforcing polymers. Herein, polyamide 6 (PA 6), BFs, and the styrene-ethylene-butylene-styrene (SEBS) copolymer were melt compounded sequentially to prepare fiber-reinforced PA 6-based composites. The results showed improved mechanical and tribological performances via the incorporation of BFs and SEBS into PA 6. Compared to neat PA 6, an average 83% increase in notched impact strength was achieved for the PA 6/SEBS/BF composites, which is mainly due to the good miscibility between SEBS and PA 6. The tensile strength of the composites, however, was only increased moderately, since the weak interfacial adhesion was not sufficiently efficient to transfer the load from the PA 6 matrix to the BFs. Interestingly, the wear rates of both the PA 6/SEBS blend and the PA 6/SEBS/BF composites were obviously lower than those of the neat PA 6. The PA 6/SEBS/BF composite with 10 wt.% of the BFs exhibited the lowest wear rate of 2.7 × 10-5 mm3/N·m, which was decreased by 95% compared to that of the neat PA 6. The facilitation of forming tribo-film with SEBS and the naturally good wear resistance of the BFs were responsible for the largely decreased wear rate. Moreover, the incorporation of SEBS and BFs into the PA 6 matrix transformed the wear mechanism from adhesive wear to abrasive wear.

Synthesis of nitrogen-doped graphene and its strengthening effect on aluminium metal matrix composite

The present study investigates the potential of nitrogen-doped graphene nanosheets (NDG) as a reinforcing material in aluminum (Al) metal matrix composites. The NDG was synthesized through a mechanochemical process involving solid-state dry ball milling of graphite with melamine. Characterization techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy were used to evaluate the properties of the NDG. For the first time, NDG was employed as a reinforcing material to improve the wettability, minimize the formation of aluminum carbide, and enhance the strength through strong interfacial bonding. The ultimate tensile and compressive yield strengths of Al/NDG composites were found to be 124% and 67% higher, respectively, with only 0.2 wt% NDG content. Furthermore, the tensile strength of the 0.2 wt% NDG/Al composite was found to be 72% higher than that of the 0.5 wt% graphene/Al composite. The fractured surface of the Al/NDG composite was investigated by XRD and FESEM techniques. XRD analysis revealed the presence of low-intensity peaks of aluminum nitride (AlN) and no evidence of aluminum carbide. The tribological properties of NDG were studied through wear rate and coefficient of friction (COF) measurements. The results showed a decrease in COF by 45% with an increase in NDG concentration from 0.1 to 0.5 wt%, and a decrease in wear rate by 25% and 71% for the same NDG concentration range. These results provide insight into the potential of NDG as an additive to improve tribological properties in aluminum-based composites. Further research is needed to understand the underlying mechanisms and optimize the performance thoroughly.

Influences of WEDM constraints on tribological and micro structural depictions of SiC-Gr strengthened Al2219 composites

The creation of this work is made by mixing various weight percentages of SiC and consistent Graphite with liquefied Al2219. For various mechanical tests including hardness, ductility, flexural, and tensile, are conducted and tested. The broken specimens of composites discovered using a filtered electron magnifying equipment (SEM). The best mechanical properties are identified in composite materials. Additionally, a similar material is focussed on the wear test. The composite with 4% SiC and 0.5% Graphite shown improved mechanical performance among the five different groupings of sic and graphite. The optimized results and the influencing parameters of electrical release WEDM were higher Material Expulsion Rate with less discomfort on the surface and boundary for wear testing also attained with decreased wear rate.

Investigations on the microstructure and properties of yttria and silicon carbide reinforced aluminium composites

Powder Metallurgy (PM) was used to synthesize SiC (0, 5, 10, 15 & 20 wt%) and 1 wt% Yttria (Y2O3) reinforced aluminium (Al) metal matrix composites. The Al–SiC–Y2O3 hybrid composites samples were prepared for density (ρ), hardness (VHN), mechanical, tribological, and microstructural studies in accordance with ASTM standards. SEM images revealed an even spreading of SiC particles throughout the Al matrix and composition was verified by the characterization techniques. The addition of SiC and Y2O3 to their respective composites improved the VHN and ‘ρ’. The compressive strength (CS) of Al–SiC–Y2O3 composites increased while increasing the SiC. The higher compression strength (405 MPa) was obtained for the Al − 1 wt% Y2O3-20 wt% SiC- hybrid composites. The thermal conductivity (K) of Al–SiC–Y2O3 samples diminishes, as the hard SiC particles are gradually added. Furthermore, it was observed that accumulative the wt% of SiC in the aluminium metal matrix (AMMC) results in a novel material with a decreased wear rate. The better properties was achieved for the samples contain 20 wt% of SiC content in Al − 1 wt% Y2O3 matrix.

Effect of MWCNTs on micromechanical and high-temperature tribological behavior of ZTA-MgO ceramic composites

Correlating the microstructure and tribo-mechanical properties is a promising approach for evaluating the performance of any newly decorated high-temperature materials. Aiming to improve the mechanical and tribological performance of zirconia toughened alumina (ZTA)− 0.6 wt% magnesium oxide (MgO) ceramic matrix, extremely low amounts (0.05 wt% and 0.1 wt%) of multi-walled carbon nanotube (MWCNT) is added into matrix. MWCNT-reinforced ZTA-0.6 wt%MgO composites are fabricated through a colloidal mixing followed by hot-press sintering at 1500 °C. The ceramic composites exhibit excellent tribo-mechanical properties attributed to the microstructural modification through the effective interaction between matrix and reinforcement phases including spinel (MgAl2O4) formation and MWCNTs. Perceptible improvement of hardness and fracture toughness ascribes to the collective strengthening mechanism. The advanced micromechanical interlocking mechanism for 0.05 wt% MWCNT-reinforced composite derives from the length reduction of MWCNTs during the powder mixing. The rolling action of MWCNT clumps evolves into a prominent three-body abrasive wear including crack bridging and crack arrest. This impeccable anti-wear and lubrication performance refer to decreasing wear rate of ∼81% and coefficient of friction of ∼29% even at 500 °C temperature making ZTA-0.6 wt%MgO-0.05 wt%MWCNT composite appropriate for high-temperature wear resistance applications.

Surface integrity and tribological behavior of 17Cr2Ni2MoVNb steel under combined carburizing treatment and ultrasonic rolling

Carburizing combined with ultrasonic surface rolling (USR) were introduced to decrease wear rate and coefficient of friction (COF) of a new type gear steel. Microstructure, microhardness, surface morphology and tribological behavior were investigated. Results indicated that specimens underwent combined treatment can generate average surface particles size of 6.67 μm, microhardness of 918 HV0.2, maximum surface compressive residual stress was −468 MPa. And wear rate of carburized specimen and specimen underwent combined treatment were 3.16 × 10−15 m3/Nm and 2.98 × 10−15 m3/Nm, respectively. Moreover, wear mechanisms of carburized specimens were three-body wear, and specimens underwent combined treatment mainly exhibited adhesive and oxidative wear.