Wear Weight Research Articles

Investigation of the Wear Behavior of Martempered 30 MnB5 Steel for Soil Tillage

The objective of this experimental study was to determine the wear resistance of moldboard plowshares produced from 30 MnB5 steel that were treated with different martempering conditions. The microstructures, the hardness distributions, and the wear behavior of the martempered 30 MnB5 steel were determined and compared with conventionally heat-treated samples in laboratory conditions. The wear losses of all martempered samples were less than that of the conventionally heat-treated samples in laboratory conditions, especially at the end of a longer-term wear experiment. The martempering process in which the steel was austenized at 960C for 35 min, held at 350C for 10 s in a salt bath, and then cooled in air produced the best results for decreasing wear loss in laboratory conditions. The martempering treatment that resulted in the lowest wear weight loss in pin-on-disc tests was selected for further testing in field conditions. The field used for the experiment was flat and free of crop residue with a uniformly dispersed soil type (sandy and sandy loam). A reversible plow was used to measure the wear. The abrasive wear losses were determined by measuring the plowshare's weight and dimensions before and after tillage. By achieving a more uniform hardness distribution, the lath-type martensitic and bainitic microstructure of the martempered plowshares significantly increased their wear resistance. The martempering process decreased the wear weight loss by 40.8% and the wear dimension loss by 38.5% compared to conventionally heat-treated plowshares in field conditions.

Investigation of the reduction of mouldboard ploughshare wear through hot stamping and hardfacing processes

The effects of the hot stamping process and different hardfacing techniques, such as shielded metal arc welding (SMAW) and gas metal arc welding (GMAW), on the abrasive wear of ploughshares were investigated under field operational conditions. The abrasive wear losses were determined by measuring the weight and dimension changes before and after tillage. The wear losses of hot-stamped and hardfaced ploughshares were less significant than those of the conventionally heat-treated ploughshare specimens used under field conditions. Conventional heat treatment and hardfacing by the SMAW process decreased the wear weight losses by 46.31% and the dimensional losses by 86.77% in comparison to the performance of the conventionally heat-treated ploughshares. These values were 36.90% and 88.17%, respectively, for conventional heat treatment and hardfacing by the GMAW process. There were no statistically significant differences between the SMAW and GMAW hardfacing processes in terms of wear losses. Hot stamping and heat treatment applications on the ploughshare also decreased wear losses by 19.03% and dimension losses by 13.82% in comparison to the conventional heat treatment process. According to the results of the overall study, hot stamping and hardfacing by SMAW and GMAW processes can be recommended as efficient solutions for decreasing the wear losses of ploughshares.

Novel Surface Treat Technology for Improving Wear-Resistant Properties of Cylinder Liner

In order to solve the problem of wear-out–failure of diesel engine cylinder, the laser-quenching and low temperature ion sulfurizing complex surface treatment technology was operated on the surface of 42MnCr52 steel. And the tribological properties of the complex layer were investigated。Experimental results indicated that the complex layer is composed of soft surface sulphide layer and sub-surface laser-quenching harden layer, represents excellent friction-reduction and wear-resistance performance at high temperature. The synergistic effect of the laser quenching-sulphide layer resulted in 20% increase in hardness, 10% reduction in friction coefficient and 50% reduction in wear weight loss, respectively, compared with those of the standard samples. The bench-test further demonstrated that this technology can improve the lubricating condition between cylinder and piston ring, and reduce both abnormity wear when the lubricating oil is deficiency at the time of start-up and sticking wear at high temperature during the operating period, and then prolong the service life of engine.

Preparation and performance of electrodeposited Ni-TiB 2-Sm 2O 3 composite coatings

Sm 2O 3 and TiB 2 were used as codeposited particles in electrodeposition Ni-TiB 2-Sm 2O 3 composite coatings to improve its performance. Ni-TiB 2-Sm 2O 3 composite coatings were electrodeposited in the nickel sulfate, hexadecylpyridinium bromide and cetyltrimethylammonium bromide solution containing TiB 2 and Sm 2O 3 particles. The content of codeposited Sm 2O 3 in the composite coating was controlled by changing the concentrations of Sm 2O 3 particles in the solution. The composite coatings were characterized with X-ray diffraction (XRD) and inductively coupled plasma-atomic emission spectrometer (ICP-AES). The effects of Sm 2O 3 content on microhardness, wear weight loss and friction coefficient of composite coatings were investigated, respectively. The microhardness of the Ni-TiB 2-Sm 2O 3 composite coatings was 19.35%, 16.58%, 2.03% higher than that of the Ni coating, Ni-Sm 2O 3 and Ni-TiB 2 composite coatings, respectively. The wear weight loss of the Ni-TiB 2-Sm 2O 3 composite coatings was 7, 2.33, 1.22 times lower than that of the Ni coating, Ni-Sm 2O 3 and Ni-TiB 2 composite coatings, respectively. The friction coefficient of the Ni coating, Ni-Sm 2O 3, Ni-TiB 2 and Ni-TiB 2-Sm 2O 3 composite coatings were 0.712, 0.649, 0.850 and 0.788, respectively. The loading-bearing capacity and the wear-reducing effect of the Sm 2O 3 particles were closely related to the content of Sm 2O 3 particles in the composite coatings.

Microstructure and Wear Resistance of the Composite Coatings Fabricated on Titanium Alloys by Laser Cladding

In situ reaction synthesized TiB reinforced titanium matrix composites were fabricated using rapid non-equilibrium synthesis techniques of laser cladding. TiB/Ti composite coating was treated on Ti-6Al-4V surface using Ti and B powder mixture by laser cladding. Microstructure and dry sliding wear behavior of the in situ synthesized TiB/Ti composite coatings were investigated by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), energy-dispersive spectroscopy (EDS), hardness tester and friction and wear tester. The composite coatings consist of Ti, TiB and intermetallic compounds. The TiB reinforcement dispersed homogeneously in the composite coatings. The wear tests show that the friction coefficient and wear weight loss ratio of the coatings is lower than that of the Ti-6Al-4V alloy. The composite coating was reinforced by the in situ synthesized TiB ceramic particles. Based on the SEM observation, effects of scan speed on hardness and wear resistance of the laser cladding coatings were investigated and discussed.

Preparation and Properties of Al<sub>2</sub>O<sub>3</sub> Ceramic Reinforced Mo-Based Composites by Al(NO<sub>3</sub>)<sub>3</sub> Precursor

To enhance the wear resistance of molybdenum alloys, Mo-based composites reinforced by Al2O3 ceramic particles were developed. Using Al(NO3)3 aqueous solution and MoO3 as raw materials, the Molybdenum powders mixed with Al2O3 particles were prepared by liquid-solid incorporation, drying, pyrolysis of Al(NO3)3 and deoxidation of MoO3 by H2. And then the Mo-based composites with 3-10vol.% Alumina were prepared by compaction and sintering at 1840°C. The morphology of the Molybdenum powder and microstructure of the composites were analyzed by SEM and XRD. The micro-hardness, density and wear property of composites were researched. The results showed that α-Al2O3 ceramic particles and Molybdenum matrix compose the composites. With the increase of Alumina content, the molybdenum powders become fine and rule, the grains of composites become fine, the microhardness of Molybdenum matrix increases, and the density first increases and then decreases. The friction coefficient of composite is scarcely affected by the alumina content. While the wear weight of the composite decrease with the increase of Alumina content. There are obvious plow furrow and abrasive dust on the worn surface, showing the abrasive wear characterization.

Wear Mechanism Analysis and Microstructure of Vanadium Carbide Coating by Thermal Diffusion Process

In this paper, the typical cold work die steel Cr12MoV was used as substrate material for vanadizing treatment. And the coating structure and bonding strength were studied. Moreover, comparison experiment of wear resistance between the coating and the substrate material was performed, and based on the experiment results, wear failure mechanism of vanadizing layer was analyzed. The results showed that vanadium carbide coating is dense, with fine grain structure and high bonding strength. These features help to improve the wear resistance of coatings. Comparision of wear performance between coating and substrate showed that vanadizing surface layer can significantly improve wear resistance of substrate material. Friction coefficient decreased from the 0.48 to 0.33 and wear weight loss decreased by 95%. Wear Failure analysis showed that the vanadium carbide layer of the wear mechanism is fatigue spalling wear.

Tribological Properties of Pb-Sn-CNTs Composite Coatings

Multi-walled carbon nanotube (MWCNT)/Pb-Sn composite coatings were prepared by electrodeposition technique. Friction coefficient and wear weight losses were investigated on a double rings apparatus using carbon steel (C: 0.45%) rings as counterparts under wet friction condition. Tribological characteristics were compared among the samples as carbon nanotubes concentration was changed in the bath. The results indicate that the composite coatings had smaller friction coefficient and weight loss than that of ordinary Pb-Sn coatings under the same work conditions. In addition, the wear performance of Pb-Sn-CNTs composite coating was optimized when the CNTs concentration in bath was 2 g L-1.

Dry Sliding Wear Behaviours of Intrinsically Sintered Micro-Arc Oxidation Coatings on Pure Aluminum

Wear behaviours of micro-arc oxidation (MAO) coatings on pure aluminum in a phosphate based electrolyte were investigated. The surface morphology, cross-section morphology and elements distribution of coatings were observed by scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). Wear test was proceeded with improved pin-on-disk tester under the dry sliding friction condition at load of 10 N. The results show that coatings structure are poly-porous and uniform, the components in the phosphate electrolyte do not participate in the formation of coatings, coatings are oxidized and sintered intrinsically. Wear weight loss of MAO coatings decrease by a factor of 20 in compare with the pure aluminum substrate, and abrasive wear assisted stripping from micro-cracking is predominant wear mechanism.

Modeling Corrosion Property of High Chromium Cast Iron under H<sub>3</sub>PO<sub>4</sub> Medium Condition Using Artificial Intelligence

The components in slurry pump suffer serious corrosion and abrasion in the phosphorus fertilizer manufacturing process because they undergo corrosion of H3PO4 medium and impact of particles at the same time. Presently, High chromium cast irons are often used to produce the components in slurry pump. In order to reveal the corrosive law, the corrosion properties of high chromium cast iron with 26wt.%Cr content (Cr26) were tested under different H3PO4 medium concentration conditions. Using back-propagation (BP) neural network, the non-linear relationship between the corrosion weight losses (W) and H3PO4 concentration, corrosion time (C, t) is established on the base of the dealing with experimental data. The results show that the well-trained BP neural network can predict the wear weight loss precisely according to H3PO4 concentration and corrosion time. The prediction results reveal that corrosion weight loss rises linearly with increasing corrosion time. The H3PO4 concentration has obvious effect on corrosion property. When H3PO4 concentration is lower than about 0.5mol/L, high chromium cast iron has well resistance to H3PO4 corrosion. However, the corrosion resistance of high chromium cast iron rapidly decreases when the H3PO4 concentration exceed about 0.8 mol/L. It is suggest the high chromium cast iron be used under the condition of H3PO4 concentration of lower 0.8 mol/L.

Experimental and theoretical investigation of running-in

In this paper, the running-in and steady-state wear in the mixed-EHL line contact problem are analytically and experimentally studied. An experimental apparatus is designed and built to investigate the transient wear process during the initial stage of contact of two rollers with fresh surfaces as well as the contact of broken-in surfaces, when wear rate becomes steady. Seven experiments are conducted with five running-in experiments on fresh rollers and two steady-state experiments on the run-in rollers. The results of experimental tests and a series of simulations of an analytical model that uses the load-sharing concept and accounts for plastic deformation of asperities during the running-in stage are presented. The comparison of experimentally measured wear weight, wear depth, surface roughness, friction coefficient, and surface temperature of these seven experiments are shown to be in good agreement with the simulation results.

Characterization of High-Temperature Abrasive Wear of Cold-Sprayed FeAl Intermetallic Compound Coating

FeAl intermetallic compound coating was prepared by cold spraying using a mechanically alloyed Fe(Al) alloy powder followed by post-spray annealing at 950 °C. The high-temperature abrasive wear test was carried out for the FeAl coating at a temperature range from room temperature to 800 °C. The high-temperature abrasive wear of a heat-resistant stainless steel 2520 was performed for comparison. It was observed that the abrasive wear weight loss of FeAl coating was proportional to wear cycles in terms of sample revolutions at the tested temperatures. It was found that with the increase of the test temperature higher than 400 °C, the wear rate of cold-sprayed FeAl coating decreased with the increase of test temperature, while the wear rate of the heat-resistant steel increased significantly. The results indicate that the high-temperature abrasive wear resistance of the cold-sprayed FeAl intermetallic coating increased with the increase of the wear temperature in a temperature range from 400 to 800 °C. The wear resistance of cold-sprayed FeAl coating was higher than that of heat-resistant 2520 stainless steel under 800 °C by a factor of 3.

Friction and wear behaviors of nanocrystalline surface layer of medium carbon steel

A nanocrystalline (nc) surface layer, which is about 30 μm thick, was fabricated on a medium carbon steel plate using high-energy shot peening (HESP). The tribological behavior of the nanocrystalline surface layer was investigated under the unlubricated slide using a ring-on-disc tester. The observation of the surface topography shows that the nanocrystalline surface layer may reduce the effect of fatigue wear and improve the friction and wear properties of medium carbon steel. Experimental results show that the friction coefficient and wear weight loss decrease and the wear resistance increases with the surface nanocrystallized samples under lower loads.

Microstructure and Wear Behaviour of Laser Induced <i>In-Situ</i> Formation of TiB<sub>x</sub> and TiC Titanium Composite Coatings

Two kinds of mixed powders:Ti-6Al-4V/B/C and Ti-6Al-4V/B4C which are pre-pasted on Ti-6Al-4V substrates separately were scanned by a 500W pulsed YAG laser to induce in situ formation of titanium composite coatings contained TiBx and TiC ceramic reinforced phases. The influences of laser processing parameters including Pulse Frequency (PF), Pulse Width (PW), Laser Power (P) and Scanning Speed (V) together with the powder proportions on the microstructure and properties of the coatings were investigated. Microstructure, phase components and micro-hardness of the coating were analyzed by OM, SEM, TEM, XRD and micro-hardness tester respectively. The optimized processing parameters of a single path laser scanned specimen in this case are as follows: PF: 15Hz, PW: 3ms, for the Ti-6Al-4V/B4C specimens the laser line energy ~12.5J/mm, for the Ti-6Al-4V/B/C specimens the laser line energy ~11J/mm. TiB and TiC ceramic were formed evenly reinforced in the matrix of Ti-6Al-4V with the morphology of needle, tiny dendrites and disperse spherical particles. The maximum micro-hardness of single-path layers is up to 750 Hv, which is over twice of that of the substrate (367Hv).The wear weight loss decreased nearly 3 times that of the substrate.

Wear Resistance of Nano-ZrO<sub>2</sub> Ceramic for Hip Joint Head Prostheses

By using the ring-block friction and wear machine, the friction and wear behavior of nano-ZrO2 ceramic test block against GCr15 steel test ring has been studied. At the same time, friction and wear test of 45# steel block against GCr15 steel ring has also been conducted for comparison. By using self-made test machine for the wear ability of the hip joint, the friction test of nano-ZrO2 ceramic hip joint head against ultra-high molecular weight polyethylene (UHMWPE) acetabulum has been done, the friction test of Co-Cr-Mo alloy hip joint head against UHMWPE acetabulum has also been made for comparison. The results show that the friction factor of nano-ZrO2 ceramic test block against GCr15 steel test ring is less 37.3% than that of 45# steel block against GCr15 steel ring, the wear weight of nano-ZrO2 ceramic test block against GCr15 steel test ring is only 0.76% of that of 45# steel block against GCr15 steel ring. The wear weight of UHMWPE acetabulum against nano-ZrO2 ceramic hip joint head is 61.5% of UHMWPE acetabulum against Co-Cr-Mo alloy hip joint head. This indicates nano-ZrO2 ceramic has good wear resistance property and is the ideal materials for artificial Hip joint head Prostheses.

The Oil Lubricated Sliding Wear Behavior of <i>In Situ</i> TiB<sub>2</sub> Partical-Reinforced Al-10Sn Matrix Composites

Al-10Sn matrix composites reinforced by TiB2 particles were fabricated by Mixed Salt Reaction in situ synthesis process. The oil lubricated sliding wear tests of composites and matrix alloy were conducted on a small thrust ring versus disc wear testing machine at room temperature under different applied loads and the wear surfaces were observed using SEM. The results indicate that the coefficient of friction, friction temperature, and wear weight loss increase with the increase of applied loads, but compared with matrix alloy, the composites exhibit better anti-friction property and higher wear resistance. The analysis of wear surface suggests that light ploughing is predominant for composites and matrix alloy at low loads, and ploughing is still predominant for composites at high loads, but adhesion and delamination are predominant for matrix alloy at high loads

Effect of rotational sliding velocity on surface friction and wear behavior in Zr-based bulk metallic glass

A Zr 55 Cu 30 Ni 5 Al 10 bulk metallic glass (BMG) with a dimension of 1 mm × 10 mm × 70 mm was prepared by using copper-mold suction casting and the effect of rotational sliding velocity ( RSV ) on the surface dry friction and wear behavior was studied at room temperature. The results showed that the grinding traces of the BMG specimens remain an amorphous structure after friction and wear behavior tests under a load of 5 N with a rotational velocity range of 200–1400 r/min through 8 min. The friction coefficients mainly locate between 0.15 and 0.35. With increasing RSV s, both average friction coefficient and wear weight loss present an upward trend. Obvious molten characteristics can be observed in all grinding traces. At lower RSV s, the wear mechanism tends to a combined action of continuous wear and surface flow, while at higher RSV s, the wear inclines to surface flow. In addition, slight oxidation and adhesion wear accompany during all friction and wear behavior tests.

Laser clad TiC reinforced NiCrBSi composite coatings on Ti–6Al–4V alloy using a CW CO 2 laser

TiC–NiCrBSi composite coatings were fabricated on Ti–6Al–4V substrate by laser cladding. Microstructure and wear properties in vacuum (10 − 5 Pa) and in atmosphere of the coatings were investigated. Three zones can be distinguished of the coatings: the clad zone, the bonding zone and the heat affected zone of the substrate. The clad zone is formed of undissolved TiC particles, precipitated TiC particles and dendrites, Cr 23C 6, CrB and TiB 2 dispersed in a matrix consisting of primary γ-Ni p and γ-Ni e + Ni 3B eutectics. The bonding zone and heat affected zone exhibited small dendrites and acicular martensite, respectively. The wear weight loss of the coatings was 11.4% as that of Ti–6Al–4V alloys in atmosphere, and 47.9% in vacuum. Analysis of the worn surfaces showed that the wear mechanisms of the coatings were abrasion wear in atmosphere, while adhesion wear and ploughed wear in vacuum.

Fatigue strength of HVOF sprayed Cr 3C 2–25NiCr and WC-10Ni on AISI 4340 steel

The fatigue strength of coated material is significantly influenced by internal residual stresses. Chromium coatings are used in applications to guarantee protection against wear and corrosion, combined with chemical resistance and good lubricity. The reduction in the fatigue strength of base material and since this technology presents detrimental environmental and health effects, resulted in the search on coatings viewed as being capable of replacing hard chrome plating. Thermally sprayed HVOF coatings are being considered to replace galvanic chromium deposits in industrial applications with, at least, comparable performance with respect to wear and corrosion resistance. The aim of the present study is to compare the influence of Cr 3C 2–25NiCr and WC–10Ni coatings applied by HVOF process and hard chromium electroplating on the fatigue strength, abrasive wear and corrosion resistance of AISI 4340 steel. S–N curves were obtained in axial fatigue tests for base material, chromium plated and HVOF coated specimens. Experimental data showed higher axial fatigue resistance for HVOF coated specimens in comparison to electroplated chromium. The wear weight loss tests indicated better results for the HVOF thermal spray processing in comparison to the chromium electroplating. An increase in the corrosion resistance of steel protected with WC–10Ni HVOF coatings occurred with increased coating thickness. For Cr 3C 2–25NiCr HVOF coating, results indicate clearly the higher salt spray resistance.

Microstructure and properties of nano-Al2O3 particle reinforced Ni–Cr–Mo–Cu composite alloying layer

In order to improve the corrosion and wear resistance of 316L stainless steel (SS) in engineering application, Ni–Cr–Mo–Cu composite alloying layer reinforced by the nano-Al 2 O 3 particles was prepared by double glow plasma alloying on 316L stainless steel surface, where Ni/nano-Al 2 O 3 was firstly predeposited by brush plating. The composition and microstructure of composite alloying layer were analyzed by means of SEM, TEM and XRD. The results indicated that under alloying temperature (1000 °C) condition, the added nano-Al 2 O 3 was partially dissolved into γ-Ni based solution matrix, resulting in γ-prime (Ni 3 Al) phase precipitation. The γ-prime phase grew in a unique crystallographic orientation relationship with the γ-Ni based solution matrix. This crystallographic relationship can be described as ( 1 1 1 ) γ -Ni // ( 1 1 1 ) γ ′ -N i 3 Al . The corrosion resistance of the composite alloying layer was investigated electrochemically in 3.5% NaCl solution and in 5% HCl solution, and 100-h immersion tests in a 20% HCl solution. Compared with Ni–Cr–Mo–Cu alloying layer, nano-Al 2 O 3 particles and in situ synthesized γ-prime phase slightly decrease the corrosion resistance of the alloying layer. The dry wear test results showed that the wear weight loss of composite alloying layer was 45% and 65% less than that of 316L stainless steel and Ni–Cr–Mo–Cu alloying layer, respectively.