Laser preparation and characterization of NiCr-MoS2-M self-lubricating wear-resistant coating

TONG Zhaopeng; SUN Guifang; FANG Xiaoyu; HUANG Xuexiang

doi:10.7510/jgjs.issn.1001-3806.2016.02.004

To improve the wear resistance of extruder screws, self-lubricating wear-resistant NiCr-MoS2-M coating was fabricated on 38CrMoAl substrates by laser cladding. Phase composition and microstructures were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Microhardness was measured with a microhardness tester. Tribological properties of the fabricated composite coatings were evaluated under dry sliding condition at room-temperature. The related data were obtained through theoretical analysis and experimental verification. XRD results show that the reinforced layer is composed of FeNi,Ni3Fe and Cr-Ni-Fe-C solid solution. According to SEM observation, the reinforced layer consists of solid solution dendrites, eutectic rich in Cr and undissolved MoS2 particles. The microhardness of the coating is about 313.7HV, about 94.32% of the matrix (332.6HV). Friction coefficient is about 0.513, about 1.63 times of the matrix (0.315). Wear loss of coatings is about 58.56110-3mm3, about 11.9 times of the matrix (4.9110-3mm3). This result is helpful for the further optimization of process parameters to improve the comprehensive mechanical properties of the reinforced layers.

Laser preparation and characterization of NiCr-MoS2-M self-lubricating wear-resistant coating

Corresponding author: SUN Guifang, gfsun@seu.edu.cn;

1. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China;

2. School of Mechanical Engineering, Southeast University, Nanjing 211189, China;

3. Jiangsu Lianguan New Material Co. Ltd., Zhangjiagang 215600, China

Received Date: 2014-12-25

Accepted Date: 2015-03-17

Available Online: 2016-03-25

Abstract: To improve the wear resistance of extruder screws, self-lubricating wear-resistant NiCr-MoS2-M coating was fabricated on 38CrMoAl substrates by laser cladding. Phase composition and microstructures were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Microhardness was measured with a microhardness tester. Tribological properties of the fabricated composite coatings were evaluated under dry sliding condition at room-temperature. The related data were obtained through theoretical analysis and experimental verification. XRD results show that the reinforced layer is composed of FeNi,Ni3Fe and Cr-Ni-Fe-C solid solution. According to SEM observation, the reinforced layer consists of solid solution dendrites, eutectic rich in Cr and undissolved MoS2 particles. The microhardness of the coating is about 313.7HV, about 94.32% of the matrix (332.6HV). Friction coefficient is about 0.513, about 1.63 times of the matrix (0.315). Wear loss of coatings is about 58.56110-3mm3, about 11.9 times of the matrix (4.9110-3mm3). This result is helpful for the further optimization of process parameters to improve the comprehensive mechanical properties of the reinforced layers.

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Reference (15)

[1]	WANG C T, ZHAO L P, GU P C, et al. Defect analysis and preventing methods of 38CrMoAlA screw[J]. Journal of Zhejiang Ocean University (Natural Science Edition), 2007, 26(3):300-302(in Chinese).
[2]	LI G S. The manufacturing domestically of extruder screw rod part[J]. Science Technology in Chemical Industry, 2006, 14(5):22-25(in Chinese).
[3]	YANG Z J. Influencing factors of the wear of conical twin screw extruders and the method to reduce wear[J]. World Plastics, 2005, 23(5):37-41(in Chinese).
[4]	ZHAO P, XIE F Z, SUN W S. Fundamentals of material science[M]. Harbin:Harbin Institute of Technology Press, 1999:238-239(in Chinese).
[5]	LIN W S, ZHANG G J, WANG H P. Research progress of laser cladding technology[J]. Heat Treatment Technology and Equipment, 2008, 29(2):1-3(in Chinese).
[6]	WANG W F, SUN F J, WANG M C. Study of Cu-base coating on aluminum alloy by laser cladding[J]. Laser Technology, 2008, 32(3):240-243(in Chinese).
[7]	HUANG D W, LI H B. Effects of laser power on the 38CrMoAl surface properties of laser cladding layer[J]. Journal of Liaoning Technical University (Natural Science Edition), 2000, 19(5):539-542(in Chinese).
[8]	DING X Y, SUN X L. Research on technology of laser cladding Ni60 alloy on 38CrMoAl steel surface[J]. Foundry Technology, 2012, 32(11):1528-1531(in Chinese).
[9]	SHAN J G, DING J C, REN J L. Microstructure and strengthening mechanism of light beam cladding layer with iron-based self-fluxing alloy powder[J]. Transactions of the China Welding Institution, 2001, 22(4):1-4(in Chinese).
[10]	HUANG C B, DU L Z, ZHANG W G. Effects of solid lubricant content on the microstructure and properties of NiCr/Cr3C2-BaF2-CaF2 composite coatings[J]. Journal of Alloys and Compounds, 2009,479(1/2):777-784.
[11]	ZHANG X F, WANG A H. Microstructure and properties of laser clad nano-Ni encapsulated h-BN/CaF2 composite coating[J]. Journal of Huazhong University of Science Technology(Natural Science Edition), 2009, 37(1):9-13(in Chinese).
[12]	LIU X B, YU G, GUO J, et al. Study on microstructure and wear resistance of plasma jet clad -Cr7C3 composite coating[J]. Transactions of Materials and Heat Treat Mental, 2006, 27(12):114-117(in Chinese).
[13]	CHEN Z Y, XU J, LIU W J. Study on microstructure and wear behaviors of MoS2/TiC/Ni composite wear-resistant coating by laser cladding[J]. Transactions of Materials and Heat Treat Mental, 2007, 28(s1):253-258(in Chinese).
[14]	ZHANG D D, SHI Y, LIU J, et al. Research on controlling the crack in laser cladding of high hardness coating[J].Applied Laser, 2014, 34(1):1-8(in Chinese).
[15]	WANG X, KWON P Y, SCHROCK D, et al. Friction coefficient and sliding wear of AlTiN coating under various lubrication conditions[J]. Wear, 2013, 304:67-76.

Laser preparation and characterization of NiCr-MoS2-M self-lubricating wear-resistant coating

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