Co-reporter:Xiao-Long Lu, Xiu-Bo Liu, Peng-Cheng Yu, Shi-Jie Qiao, Yong-Jie Zhai, Ming-Di Wang, Yao Chen, Dong Xu
Optics & Laser Technology 2016 Volume 78(Part B) pp:87-94
Publication Date(Web):April 2016
DOI:10.1016/j.optlastec.2015.10.005
•Novel self-lubricating anti-wear composite coatings were fabricated on Ti6Al4V.•The coatings mainly consist of reinforced carbides, borides and hBN solid lubricant.•The coatings with the addition of hBN possessed superior properties than without.Ni60-hBN composite coatings with varying hBN content were prepared on Ti6Al4V substrates by laser cladding. The composite coatings with no cracks and few pores are bonded metallurgically with the substrates. The phase composition and microstructure of the composite coatings were investigated. The tribological properties of the composite coatings were evaluated under dry sliding wear test conditions at 20 °C, 300 °C and 600 °C, respectively. The microhardness gradually increased from the bottom to the top of the coating and increased with increasing of hBN content. The laser clad Ni60-10%hBN coating exhibits excellent tribological behavior at high temperatures (300 °C and 600 °C).
Co-reporter:Peng-Cheng Yu, Xiu-Bo Liu, Xiao-Long Lu, Shi-Jie Qiao, Yong-Jie Zhai, Gang-Xian Zhu, Yong-Guang Wang and Yao Chen
RSC Advances 2015 vol. 5(Issue 93) pp:76516-76525
Publication Date(Web):01 Sep 2015
DOI:10.1039/C5RA14732H
In order to improve the high-temperature wear and oxidation resistance of Ti6Al4V alloys simultaneously, NiCrBSiFe composite coatings were deposited on a Ti6Al4V alloy by laser cladding. The microstructure, tribological properties and high-temperature oxidation resistance of the composite coatings were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and an energy dispersive spectrometer (EDS). The results indicate that the combination between cladding zone and substrate is metallurgical bonding, and the coatings have few pores, and are crack free and homogeneous structures. In situ synthetic TiC, TiB2 and CrB particulates-reinforced γ-(Ni, Cr, Fe) matrix composite coatings are formed. The average micro-hardness of the composite coating is 950 HV0.5, and it is almost three times that of the substrate. The laser clad coatings possess better tribology properties than Ti6Al4V alloys at all test temperatures (RT, 600 °C) and the formation of dense oxide layers played an important role in improving the high temperature oxidation resistance of Ti6Al4V alloys.
Co-reporter:Xiao-Long Lu, Xiu-Bo Liu, Peng-Cheng Yu, Yong-Jie Zhai, Shi-Jie Qiao, Ming-Di Wang, Yong-Guang Wang, Yao Chen
Applied Surface Science 2015 Volume 355() pp:350-358
Publication Date(Web):15 November 2015
DOI:10.1016/j.apsusc.2015.07.138
Highlights
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Self-lubricating anti-wear composite coatings were fabricated by laser cladding.
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Effects of heat treatment on the coatings had been investigated systemically.
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Coating after heat treatment for 1 h presented the best tribological behaviors.
Co-reporter:Jian Luo;Zhan-Feng Xiang
Journal of Materials Engineering and Performance 2015 Volume 24( Issue 5) pp:1881-1889
Publication Date(Web):2015 May
DOI:10.1007/s11665-015-1466-5
Laser deposition was adopted to prepare novel Ni-based solid solution (γ-NiCrAlTi)/ TiC/α-Ti/CaF2 high-temperature self-lubricating wear resistant composite coating on Ti6Al4V alloy. Microstructure, micro-hardness, wear behavior, and counter-body effect of the coating were investigated systematically. It can be seen that the coating mainly consists of γ-NiCrAlTi, TiC, α-Ti, and small fine CaF2 particles. Average micro-hardness of the coating is 1023 HV0.3, which is about three-factor higher than that of Ti6Al4V substrate (380 HV0.3). The friction coefficient and wear rate of the coating decrease at all test temperatures to different extents with respect to the substrate. The improvement in wear resistance is believed to be the combined effects of the γ-NiCrAlTi solid solution, the dominating anti-wear capabilities of the reinforced TiC carbides, and the self-lubricating property of CaF2.
Co-reporter:Zhan-Feng Xiang, Xiu-Bo Liu, Jia Ren, Jian Luo, Shi-Hong Shi, Yao Chen, Gao-Lian Shi, Shao-Hua Wu
Applied Surface Science 2014 Volume 313() pp:243-250
Publication Date(Web):15 September 2014
DOI:10.1016/j.apsusc.2014.05.196
Highlights
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A novel high temperature self-lubricating wear-resistant coating was fabricated.
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TiC carbides and self-lubricant CaF2 were “in situ” synthesized in the coating.
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The coating with the addition of CaF2 possessed superior properties than without.
Co-reporter:Xiu-Bo Liu, Hai-Qing Liu, Xiang-Jun Meng, Cheng-Feng Sun, Ming-Di Wang, Long-Hao Qi, Gao-Lian Shi, Shao-Hua Wu
Materials Chemistry and Physics 2014 Volume 143(Issue 2) pp:616-621
Publication Date(Web):15 January 2014
DOI:10.1016/j.matchemphys.2013.09.043
•The composite coating had excellent high-temperature (600 °C) phase stability.•The average microhardness of the aged coating was slightly decreased.•The tribological properties were not significantly affected by aging treatment.The NiCr/Cr3C2–WS2 high-temperature self-lubrication wear resistant composite coatings were fabricated on substrate of a hot-rolled AISI304 austenitic stainless steel by laser cladding. The high-temperature phase stability of the composite coatings was evaluated by aging at 600 °C for 10 h, 30 h, 50 h, and the microstructures of the as-laser clad and aged coatings were examined by means of XRD, SEM, EDS, respectively. The sliding wear resistance of the as-laser clad and aged coatings was evaluated at 600 °C. The results show that NiCr/Cr3C2–WS2 composite coating has excellent high-temperature phase stability, the γ-(Fe,Ni)/Cr7C3 eutectic phases, Cr7C3 and (Cr,W)C hard phases, CrS/WS2 mixed solid lubricant phases all existed in the as-laser clad and aged coatings. The volume fraction of eutectic phases decreased gradually with the increasing of aged time due to their dissolution. The microhardness of the aged coating decreased slightly after aging the coating 50 h at 600 °C due to the dissolution of the eutectic phases and notable breaking or granulation of the Cr7C3 hard phase, but the tribological properties were not significantly affected by aging treatment.
Co-reporter:Xiu-Bo Liu, Xiang-Jun Meng, Hai-Qing Liu, Gao-Lian Shi, Shao-Hua Wu, Cheng-Feng Sun, Ming-Di Wang, Long-Hao Qi
Materials & Design 2014 55() pp: 404-409
Publication Date(Web):March 2014
DOI:10.1016/j.matdes.2013.09.038
•A novel high temperature self-lubricating anti-wear composite coating was fabricated.•Reinforced carbides as well as self-lubricating sulfides were in situ synthesized.•Microhardness of the Ti–6Al–4V substrate was significantly improved.•Friction coefficient and wear rate of the composite coating were greatly reduced.To enhance the wear resistance and friction-reducing capability of titanium alloy, a process of laser cladding γ-NiCrAlTi/TiC + TiWC2/CrS + Ti2CS coatings on Ti–6Al–4V alloy substrate with preplaced NiCr/Cr3C2–WS2 mixed powders was studied. A novel coating without cracks and few pores was obtained in a proper laser processing. The composition and microstructure of the fabricated coating were examined by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) techniques, and tribological properties were evaluated using a ball-on-disc tribometer under dry sliding wear test conditions at 20 °C (room-temperature), 300 °C, 600 °C, respectively. The results show that the coating has unique microstructure consisting of α-Ti, TiC, TiWC2, γ-NiCrAlTi, Ti2CS and CrS phases. Average microhardness of the composite coating is 1005 HV0.2, which is about 3-factor higher than that of Ti–6Al–4V substrate (360 HV0.2). The friction coefficient and wear rate of the coating are greatly decreased due to the combined effects of the dominating anti-wear capabilities of reinforced TiC and TiWC2 carbides and the CrS and Ti2CS sulfides which have excellent self-lubricating property.
Co-reporter:Xiu-Bo Liu, Chen Zheng, Yuan-Fu Liu, Ji-Wei Fan, Mao-Sheng Yang, Xiang-Ming He, Ming-Di Wang, Hong-Bing Yang, Long-Hao Qi
Journal of Materials Processing Technology 2013 Volume 213(Issue 1) pp:51-58
Publication Date(Web):January 2013
DOI:10.1016/j.jmatprotec.2012.07.017
In order to inhibit its decomposition and improve its compatibility with the metal matrix during laser cladding, WS2 powder was encapsulated with a layer of micro Ni–P by electroless plating. The microstructure and tribological properties of the NiCr–Cr3C2/30%WS2 and NiCr–Cr3C2/30%WS2(Ni–P) high temperature self-lubricating wear-resistant composite coatings at RT (room temperature), 300 °C and 600 °C were investigated, respectively. It was found that the NiCr–Cr3C2/30%WS2(Ni–P) coating had a microstructure consisting of primary Cr7C3 dendrite, γ-(Fe,Ni)/Cr7C3 eutectic and solid lubricant particles WS2 and CrS, Ni–P electroless plating had decreased the decomposition of WS2 to some extent, the WS2 solid lubricant particles dispersed in the ductile γ-(Fe,Ni)/Cr7C3 matrix. Friction and wear experiments indicated that the tribological properties of the NiCr–Cr3C2/30%WS2(Ni–P) coating was better than that of NiCr–Cr3C2/30%WS2 coating, the NiCr–Cr3C2/30%WS2(Ni–P) coating presents lower friction coefficient at RT and 300 °C and lower wear rate from RT to the elevated temperature of 600 °C.Highlights► A novel approach of Ni–P electroless plating was employed to encapsulated the solid lubricants WS2. ► The coating added with WS2(Ni–P) has a lower microhardness because of the formation of more volume fraction of relatively soft Ni based solid solution. ► The coating added with WS2(Ni–P) has a lower friction coefficient at room temperature, 300 °C, and a lower wear rate at all test temperatures. ► Ni–P electroless plating had inhibited the decomposition of WS2 and increased the compatibility with the metal matrix to some extent.
Co-reporter:Xiu-Bo Liu, Hai-Qing Liu, Yuan-Fu Liu, Xiang-Ming He, Cheng-Feng Sun, Ming-Di Wang, Hong-Bing Yang, Long-Hao Qi
Composites Part B: Engineering 2013 Volume 53() pp:347-354
Publication Date(Web):October 2013
DOI:10.1016/j.compositesb.2013.05.032
NiCr/Cr3C2–WS2–CaF2 mixed powders were designed and aimed to fabricate high temperature self-lubricating wear-resistant composite coating by laser cladding. The friction and wear properties of the coating were investigated under different temperatures and loads against Si3N4 ceramic ball. Results show that friction coefficient decreases with the increasing temperature while the wear rate firstly decreases and then increases with the increasing temperature. Both the friction coefficient and wear rate firstly decreases and then slightly increases with the increasing normal load. The coating exhibits relatively excellent tribological behavior under moderate temperature and moderate normal load.
Co-reporter:Mao-Sheng Yang, Xiu-Bo Liu, Ji-Wei Fan, Xiang-Ming He, Shi-Hong Shi, Ge-Yan Fu, Ming-Di Wang, Shu-Fa Chen
Applied Surface Science 2012 Volume 258(Issue 8) pp:3757-3762
Publication Date(Web):1 February 2012
DOI:10.1016/j.apsusc.2011.12.021
Abstract
The high temperature self-lubricating wear-resistant NiCr/Cr3C2–30%WS2 coating and wear-resistant NiCr/Cr3C2 coating were fabricated on 0Cr18Ni9 austenitic stainless steel by laser cladding. Phase constitutions and microstructures were investigated, and the tribological properties were evaluated using a ball-on-disc wear tester under dry sliding condition at room-temperature (17 °C), 300 °C and 600 °C, respectively. Results indicated that the laser clad NiCr/Cr3C2 coating consisted of Cr7C3 primary phase and γ-(Fe,Ni)/Cr7C3 eutectic colony, while the coating added with WS2 was mainly composed of Cr7C3 and (Cr,W)C carbides, with the lubricating WS2 and CrS sulfides as the minor phases. The wear tests showed that the friction coefficients of two coatings both decrease with the increasing temperature, while the both wear rates increase. The friction coefficient of laser clad NiCr/Cr3C2–30%WS2 is lower than the coating without WS2 whatever at room-temperature, 300 °C, 600 °C, but its wear rate is only lower at 300 °C. It is considered that the laser clad NiCr/Cr3C2–30%WS2 composite coating has good combination of anti-wear and friction-reducing capabilities at room-temperature up to 300 °C.
Co-reporter:Xiang-Ming He, Xiu-Bo Liu, Ming-Di Wang, Mao-Sheng Yang, Shi-Hong Shi, Ge-Yan Fu, Shu-Fa Chen
Applied Surface Science 2011 Volume 258(Issue 1) pp:535-541
Publication Date(Web):15 October 2011
DOI:10.1016/j.apsusc.2011.08.072
Abstract
In order to improve the high-temperature wear resistance of austenitic stainless steel, a wear resistant composite coating reinforced with hard (Cr,Fe)7C3 carbide and toughened by ductile γ-(Ni,Fe)/(Cr,Fe)7C3 eutectic matrix was fabricated by a novel central hollow laser cladding technique. The constituent phases and microstructure as well as high-temperature tribological behaviors of the Ni-based coating were investigated, respectively, and the corresponding wear mechanisms were discussed. It has been found that the composite coating exhibits superior wear resistance than substrate either at ambient or high temperatures. The coating shows better sliding wear resistance at 600 °C than 300 °C owing to high-temperature stability of the reinforced carbide and polishing effect as well as formation of continuous lubricious films, which implied it has large potential industrial applications at relatively higher temperatures.
