Friction and Wear Behaviors of Plasma Sprayed Conventional and Nanostructured WC-12Co Coatings at Elevated Temperature

ABSTRACTPlasma sprayed deposits of alumina are normally of the metastable gamma phase, which transforms to alpha upon heating to an elevated temperature. The poor thermal conductivity of gamma phase is improved by transforming to alpha, but the improvement is restricted by the fragmented nature of the structure, a consequence of alpha being a denser phase than gamma.Alpha phase has been reported to form when deposits are made on preheated substrates. It was found that reducing the distance between gun and deposition surface, thereby raising the temperature of the latter, resulted in transforming gamma to alpha, and as the temperature continued to rise, alpha formed directly from the liquid. The thermal conductivity of alpha formed directly from the liquid is 0.27 Watt/cm K at 323 K, which approaches the thermal conductivity given for 99.5% pure, 98% dense, polycrystalline alpha alumina.

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CJ89-47. The friction and wear mechanisms of plasma sprayed ceramic coatings at 450°C

International Journal of Mechanical Sciences ◽

10.1016/0020-7403(90)90131-2 ◽

1990 ◽

Vol 32 (2) ◽

pp. 161

Keyword(s):

Wear Mechanisms ◽

Friction And Wear ◽

Ceramic Coatings ◽

Friction And Wear Mechanisms ◽

Plasma Sprayed

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Tribological Behavior of Si3N4/Ti3SiC2Contacts Lubricated by Lithium-Based Ionic Liquids

Advances in Materials Science and Engineering ◽

10.1155/2014/863230 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Haizhong Wang ◽

Zenghong Song ◽

Dan Qiao ◽

Dapeng Feng ◽

Jinjun Lu

Keyword(s):

Ionic Liquids ◽

Elevated Temperature ◽

Tribological Properties ◽

Friction And Wear ◽

Room Temperature ◽

Tribological Behavior ◽

Tribological Performance ◽

Experimental Conditions ◽

Thermal Stabilities ◽

Protective Films

The tribological performance of Si3N4ball sliding against Ti3SiC2disc lubricated by lithium-based ionic liquids (ILs) was investigated using an Optimol SRV-IV oscillating reciprocating friction and wear tester at room temperature (RT) and elevated temperature (100°C). Glycerol and the conventional imidazolium-based IL 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (L-F106) were used as references under the same experimental conditions. The results show that the lithium-based ILs had higher thermal stabilities than glycerol and lower costs associated with IL preparation than L-F106. The tribotest results show that the lithium-based ILs were effective in reducing the friction and wear of Si3N4/Ti3SiC2contacts. [Li(urea)]TFSI even produced better tribological properties than glycerol and L-F106 both at RT and 100°C. The SEM/EDS and XPS results reveal that the excellent tribological endurance of Si3N4/Ti3SiC2contacts lubricated by lithium-based ILs was mainly attributed to the formation of surface protective films composed of various tribochemical products.

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Effect of Ni/MoS2 Addition on Microstructure and Properties of Supersonic Plasma-Sprayed Ni-Based Composite Coatings

Materials Science ◽

10.5755/j02.ms.29299 ◽

2021 ◽

Author(s):

Xinsheng WANG ◽

Wenbin HE ◽

Junjian HOU ◽

Kun LIU ◽

Xihao YAN

Keyword(s):

Friction And Wear ◽

Composite Coatings ◽

Tool Material ◽

Friction Reduction ◽

Fatigue Performance ◽

Fatigue Properties ◽

Wear Properties ◽

Wear Performance ◽

Supersonic Plasma ◽

Plasma Sprayed

Abnormal tool wear is a significant problem encountered in machining. MoS2 has the function of friction reduction; thus, to mitigate friction, two Ni-based coatings, Ni60 and Ni60 + 15 wt.% Ni/MoS2, were obtained on tungsten steel using supersonic plasma technology. The microstructure, phase structure, microhardness, fatigue properties, and friction and wear properties of the two coatings were characterized. The results show that the two plasma-sprayed Ni-based coatings have desirable structures. The addition of Ni-coated MoS2 can effectively improve the hardness of the coatings, with values reaching as high as 735 HV. The speed of rotation of the friction ball was set as 200 r/min, and the cutting force was 201.6 N. The fatigue performance as well as the friction and wear performance of the coating are simulated using ANSYS. The fatigue performance is improved by 12.6 % after adding 15 wt.% Ni/MoS2, and the friction system of the coating becomes stable after 25 min of contact. The addition of 15 wt.% Ni/MoS2 can effectively improve the performance of the tool material.

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