A multilayer film,composed by ZrN‒Ag(20 nm)and Mo‒S‒N(10 nm)layers,combining the intrinsic lubricant characteristics of each layer was deposited using DC magnetron sputtering system,to promote lubrication in a wide-ra...A multilayer film,composed by ZrN‒Ag(20 nm)and Mo‒S‒N(10 nm)layers,combining the intrinsic lubricant characteristics of each layer was deposited using DC magnetron sputtering system,to promote lubrication in a wide-range of temperatures.The results showed that the ZrN‒Ag/Mo‒S‒N multilayer film exhibited a sharp interface between the different layers.A face-centered cubic(fcc)dual-phases of ZrN and Ag co-existed in the ZrN‒Ag layers,whilst the Mo‒S‒N layers displayed a mixture of hexagonal close-packed MoS_(2)(hcp-MoS_(2))nano-particles and an amorphous phase.The multilayer film exhibited excellent room temperature(RT)triblogical behavior,as compared to the individual monolayer film,due to the combination of a relative high hardness with the low friction properties of both layers.The reorientation of MoS_(2)parallel to the sliding direction also contributed to the enhanced anti-frictional performance at RT.At 400℃,the reorientation of MoS_(2)as well as the formation of MoO_(3)phase were responsible for the lubrication,whilst the hard t-ZrO_(2)phase promoted abrasion and,consequently,led to increasing wear rate.At 600℃,the Ag_(2)MoO_(4)double-metal oxide was the responsible for the low friction and wear-resistance;furthermore,the observed transformation from t-ZrO_(2)to m-ZrO_(2),could also have contributed to the better tribological performance.展开更多
This paper discusses the effect of ageing on the thermally induced martensitic transformation and its reverse transformation and shape memory effect of Fe-24Mn-5Si-8Co-4Mo shape memory alloy:the precipitation of Fe 2...This paper discusses the effect of ageing on the thermally induced martensitic transformation and its reverse transformation and shape memory effect of Fe-24Mn-5Si-8Co-4Mo shape memory alloy:the precipitation of Fe 2Mo particles increases the hardness and strength of the alloy as ageing goes on;ageing increases the transformation temperatures;ageing improves,the SME of the alloy so remarkably that a maximum shape recovery ratio is obtained while ageing at 600℃.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52171071,51801081,and 52071159)national funds through FCT of Portugal-Fundação para a Ciência e a Tecnologia,under a scientific contract of 2021.04115.CEECIND,and the project of UIDB/00285/2020,LA/0112/2020,MCTool21-ref.“POCI-01-0247-FEDER-045940”cofinanced via FEDER and FCT-Fundação para a Ciência e a Tecnologia(COMPETE),Outstanding University Young Teachers of“Qing Lan Project”of Jiangsu Province of China,Excellent Talents of“Shenlan Project”of Jiangsu University of Science of China.
文摘A multilayer film,composed by ZrN‒Ag(20 nm)and Mo‒S‒N(10 nm)layers,combining the intrinsic lubricant characteristics of each layer was deposited using DC magnetron sputtering system,to promote lubrication in a wide-range of temperatures.The results showed that the ZrN‒Ag/Mo‒S‒N multilayer film exhibited a sharp interface between the different layers.A face-centered cubic(fcc)dual-phases of ZrN and Ag co-existed in the ZrN‒Ag layers,whilst the Mo‒S‒N layers displayed a mixture of hexagonal close-packed MoS_(2)(hcp-MoS_(2))nano-particles and an amorphous phase.The multilayer film exhibited excellent room temperature(RT)triblogical behavior,as compared to the individual monolayer film,due to the combination of a relative high hardness with the low friction properties of both layers.The reorientation of MoS_(2)parallel to the sliding direction also contributed to the enhanced anti-frictional performance at RT.At 400℃,the reorientation of MoS_(2)as well as the formation of MoO_(3)phase were responsible for the lubrication,whilst the hard t-ZrO_(2)phase promoted abrasion and,consequently,led to increasing wear rate.At 600℃,the Ag_(2)MoO_(4)double-metal oxide was the responsible for the low friction and wear-resistance;furthermore,the observed transformation from t-ZrO_(2)to m-ZrO_(2),could also have contributed to the better tribological performance.
文摘This paper discusses the effect of ageing on the thermally induced martensitic transformation and its reverse transformation and shape memory effect of Fe-24Mn-5Si-8Co-4Mo shape memory alloy:the precipitation of Fe 2Mo particles increases the hardness and strength of the alloy as ageing goes on;ageing increases the transformation temperatures;ageing improves,the SME of the alloy so remarkably that a maximum shape recovery ratio is obtained while ageing at 600℃.
