Study on the Microstructures and Wear Resistance of ZG30 Steel Surface Layer

2011 ◽  
Vol 117-119 ◽  
pp. 1271-1275
Author(s):  
Ai Qin Wang ◽  
Jing Pei Xie ◽  
Wen Yan Wang ◽  
Ji Wen Li

The WC and high-Cr cast iron layer were obtained on the surface of ZG30 steel by infiltration casting process, so the surface alloying of ZG30 steel was realized. The microstructures and phase structures of penetrating layer were studied by SEM, TEM, XRD, the hardness of the test material was measured by the hardness tester, and the wear resistance was tested by wear test machine. The mechanism of alloyed layer forming was analyzed. The effects of WC contents on the wear resistance of alloyed layer were studied. The results show that the layer is dense, without pores, slag and other defects, the thickness of the alloyed layer is about 6-7mm, and the penetrating layer and matrix are metallurgical bonding. The maximum hardness of the alloyed layer surface is 820Hv. When the content of WC is 15%, the penetrating layer has the highest wear resistance which is 18.8 times as high as the matrix.

2017 ◽  
Vol 24 (4) ◽  
pp. 541-546 ◽  
Author(s):  
Hongxia Zhang ◽  
Huijun Yu ◽  
Chuanzhong Chen

AbstractThe composite coatings were fabricated by laser cladding Ni60A/B4C pre-placed powders on the surface of Ti-6Al-4V alloy for improving wear resistance and hardness of the substrate. In this research, the composite coatings were studied by means of X-ray diffraction, scanning electron microscope and energy dispersive spectrometer. The sliding wear tests were performed using MM200 wear test machine. The hardness of the coatings was tested by HV-1000 hardness tester. After laser cladding, it was found that there was a good metallurgical bond between the laser cladding coating and Ti-6Al-4V substrate. The composite coatings were mainly composed of the matrix of γ-Ni and a little Ni3Ti and the reinforcements of TiB2, TiC and CrB. The hardness of the sample of Ni60A-5B4C was approximately 2.5–3.5 times that of the Ti-6Al-4V substrate. The hardness of the sample of Ni60A-10B4C was 30% higher than that of sample 1. The wear resistance of samples 1 and 2 were 11 times and 10 times that of the substrate, respectively.


2015 ◽  
Vol 22 (03) ◽  
pp. 1550044 ◽  
Author(s):  
H. X. ZHANG ◽  
H. J. YU ◽  
C. Z. CHEN

The composite coatings were fabricated by laser cladding Al / TiN pre-placed powders on Ti –6 Al –4 V substrate for enhancing wear resistance and hardness of the substrate. The composite coatings were analyzed by means of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The sliding wear tests were performed by MM200 wear test machine. The hardness of the coatings was tested by HV-1000 hardness tester. After laser cladding, it was found that there was a good metallurgical bond between the coating and the substrate. The composite coatings were mainly composed of the matrix of β- Ti  ( Al ) and the reinforcements of titanium nitride ( TiN ), Ti 3 Al , TiAl and Al 3 Ti . The hardness and wear resistance of the coatings on four samples were greatly improved, among which sample 4 exhibited the highest hardness and best wear resistance. The hardness of the coating on sample 4 was approximately 2.5 times of the Ti –6 Al –4 V substrate. And the wear resistance of sample 4 was four times of the substrate.


2019 ◽  
Vol 26 (10) ◽  
pp. 1950077 ◽  
Author(s):  
H. X. ZHANG ◽  
J. J. DAI ◽  
Z. W. MA ◽  
X. Y. WANG ◽  
N. L. ZHANG

In this paper, TiC reinforced composite coatings were fabricated on TC4 alloy by laser cladding Ti,Al,Si, TiC and Y2O3 mixed powders. Microstructures and properties of the clad coatings with and without Y2O3 were discussed by comparative experiments. SEM, XRD and EDS were employed to discover the microstructures and the composition of phases. The hardness and wear resistance of the coatings were tested by the MM200 wear test machine and a HV-1000 digital hardness tester, respectively. The results showed that the coating was majorly composed of Ti5Si3, Ti7Al5[Formula: see text], Ti3AlC2, Ti3Al, Al3Ti, TiAl and Y2O3. The dilution zone exhibited a metallurgical bonding without pores and cracks. Compared with the TC4 substrate, the hardness and wear resistance of the coatings were heightened by 5–6 and 4.5–5.8 times, respectively. With 2.0[Formula: see text]wt.% Y2O3 addition, the microstructure of the coating was refined significantly, and the microhardness and dry sliding wear resistance were enhanced further. The effects of Y2O3 were attributed to heterogeneous nucleation of the residual Y2O3.


2017 ◽  
Vol 24 (Supp01) ◽  
pp. 1850009 ◽  
Author(s):  
H. X. ZHANG ◽  
H. J. YU ◽  
C. Z. CHEN ◽  
J. J. DAI

In order to improve the wear resistance of Ti alloys, different mass ratios of Ti-Si-Al powders were designed to fabricate hard phases reinforced intermetallic matrix composite coatings on the Ti-6Al-4V substrate by laser cladding. The corresponding coatings were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and high resolution transmission microscopy (HRTEM). The HV-1000 hardness tester and MM200 wear test machine were employed to test the hardness and the wear resistance of the composite coatings, respectively. The composite coatings mainly consisted of the reinforcements of Ti5Si3, Ti3AlC2 and Ti7Al5Si[Formula: see text] and the matrix of Ti3Al, TiAl, TiAl3 and [Formula: see text]-Ti. The micro-hardness of the Ti-35Al-15Si coating was from 956 HV[Formula: see text] to 1130 HV[Formula: see text], which was approximately 3–4 times of the substrate and the highest in the three samples. The wear rate of the Ti-35Al-15Si coating was 0.023[Formula: see text]cm3[Formula: see text][Formula: see text][Formula: see text]min[Formula: see text], which was about 1/4 of the Ti-6Al-4V substrate. It was the lowest in the three samples.


2010 ◽  
Vol 177 ◽  
pp. 643-646 ◽  
Author(s):  
Wen Yan Wang ◽  
Xiao Ming Dong ◽  
Jing Pei Xie ◽  
Jing Xu ◽  
Luo Li Li

Using sub-micron WC/Co metal ceramic composite as coating materials for laser alloying experiments to prepare high hardness and wear resistance alloyed layer on the surface of 9CrSi. The microstructures of laser-alloyed coating were detected by SEM and XRD. The microhardness and wear-resistance of the coatings were also investigated. The results indicate that, the laser alloyed layer and substrate form a good metallurgical bonding. The analysis of SEM reveal that the alloyed layer can be divided into alloyed zone, heat affected zone and substrate zone. The alloyed zone is composed by martensite, netted dendrite carbides and small carbide particles, the netted dendrite carbides distribute in the martensitic and the small carbide particles dispersed in the gap of the netted dendrite. The heat affected zone is consisted of retained austenite and martensite. There is no significant change in the matrix zone.The coating has a high hardness of 900HV0.2 , and the abrasion loss of the alloyed coating is just one ninth of that of 9CrSi. The wear resisitance of the alloyed coating relative to the substrate 9CrSi has significantly improved.


Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 712
Author(s):  
Mesay Alemu Tolcha ◽  
Moera Gutu Jiru ◽  
Hirpa Gelgele Lemu

Laser surface alloying is one of the recent technologies used in the manufacturing sector for improving the surface properties of metals. Aluminum alloys are key materials in the manufacturing sector. This favors their high demand in many industries. In this study investigation, the surface alloying of pure aluminum was conducted using a CO2 laser. Four types of alloying powders were used with a 2:1:1 combination of copper, magnesium, and manganese. The hardness of the alloyed zones of Al-CuMgMn increased by 2 to 7 times at a 1.7 kW processing laser power. To assess the rate of wear for the alloyed samples, a modified Lancaster wear coefficient was considered. When the pin-on-disc wear test at 10 N and 20 N loads was analyzed with different sliding speeds, a reduction in wear by 30–50% appeared due to surface alloying. The result shows good insight into the wear behavior. In the same way, microstructure and surface morphology studies displayed a good metallurgical bonding without defects. In a statistical sense, the friction and wear behavior matched with an asperity-based model. The experimental results revealed that laser surface alloy has more wear resistance.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 46
Author(s):  
Hu Xu ◽  
Junsheng Sun ◽  
Jun Jin ◽  
Jijun Song ◽  
Chi Wang

At present, most Mo2FeB2-based cermets are prepared by vacuum sintering. However, vacuum sintering is only suitable for ordinary cylinder and cuboid workpieces, and it is difficult to apply to large curved surface and large size workpieces. Therefore, in order to improve the flexibility of preparing Mo2FeB2 cermet, a flux cored wire with 70% filling rate, 304 stainless steel, 60 wt% Mo powder and 40 wt% FeB powder was prepared. Mo2FeB2 cermet was prepared by an arc cladding welding metallurgy method with flux cored wire. In this paper, the microstructure, phase evolution, hardness, wear resistance and corrosion resistance of Mo2FeB2 cermets prepared by the vacuum sintering (VM-Mo2FeB2) and arc cladding welding metallurgy method (WM-Mo2FeB2) were systematically studied. The results show that VM-Mo2FeB2 is composed of Mo2FeB2 and γ-CrFeNi.WM-Mo2FeB2 is composed of Mo2FeB2, NiCrFe, MoCrFe and Cr2B3. The volume fraction of hard phase in WM-Mo2FeB2 is lower than that of VM-Mo2FeB2, and its hardness and corrosion resistance are also slightly lower than that of VM-Mo2FeB2, but there are obvious pores in the microstructure of VM-Mo2FeB2, which affects its properties. The results show that WM-Mo2FeB2 has good diffusion and metallurgical bonding with the matrix and has no obvious pores. The microstructure is compact and the wear resistance is better than that of VM-Mo2FeB2.


2019 ◽  
Vol 130 ◽  
pp. 01005
Author(s):  
Cindy Retno Putri ◽  
Anne Zulfia Syahrial ◽  
Salahuddin Yunus ◽  
Budi Wahyu Utomo

The goal of this research is to improve the mechanical properties such as strength, hardness and wear resistance for automotive application such as brake shoe and bearings due to high cycle, load and impact during their usage. Therefore, another alloying element or reinforcement addition is necessary. In this work, the composites are made by ADC 12 (Al-Si aluminum alloy) as the matrix and reinforced with micro SiC through stir casting process and TiB is added various from (0.04, 0.06, 0.15, 0.3 and 0.5) wt.% that act as grain refiners and 5 wt.% of Mg is added to improve the wettability of the composites. The addition of TiB improves the mechanical properties because the grain becomes finer and uniform, and the addition of Mg makes the matrix and reinforce have better adhesion. The results obtained that the optimum composition was found by adding 0.15 wt.% of TiB with tensile strength improve from 98 MPa to 136.3 MPa, hardness from 35 to 53 HRB and wear rate reduced from 0.006 2 mm3 s−1 to 0.002 3 mm3 s−1 respectively.


2011 ◽  
Vol 415-417 ◽  
pp. 170-173
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Yi Chao Ding ◽  
Yi San Wang

A wear resistant TiC-Cr7C3/Fe surface composite was produced by cast technique and in-situ synthesis technique. The microstructure and dry-sliding wear behavior of the surface composite was investigated using scanning electron microscope(SEM), X-ray diffraction(XRD) and MM-200 wear test machine. The results show that the surface composite consists of TiC and Cr7C3as the reinforcing phase, α-Fe and γ-Fe as the matrix. The surface composite has excellent wear-resistance under dry-sliding wear test condition with heavy loads.


2018 ◽  
Vol 934 ◽  
pp. 100-104
Author(s):  
Yuan Ching Lin ◽  
Ji Wei Gong

In this investigation, the effects of different heat treatment conditions on the mechanical properties of high carbon tool steel (SK2) were explored. Experimental results indicated that immediately doing deep cryogenic treatment can effectively reduce retained austenite after quenching. The moment of the holding time for the cryogenic treatment was extended can promote the fine carbides precipitated, and thus increased its hardness. The results of X-ray diffraction showed that the carbides in the matrix included Fe3C and Fe7C3.The wear test results demonstrated that the specimen with Q-T1hr-C24hr-T1hr treatment has the highest wear resistance than the others, which was caused by the effect of several tempering processes to improve toughness of the matrix and to precipitate considerable quantities of the fine carbides.


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