Nickel-based alloys applied in marine environments often face multiple challenges of stress,corrosion and wear.In this work,heterostructured NiCrTi alloy was prepared by spark plasma sintering coarse Ni20Cr and ultraf...Nickel-based alloys applied in marine environments often face multiple challenges of stress,corrosion and wear.In this work,heterostructured NiCrTi alloy was prepared by spark plasma sintering coarse Ni20Cr and ultrafine Ti powders.Apart that some are dissolved into the nickel alloy,Ti powders react in situ with Ni20Cr during sintering to form hard intermetallic Ni_(3)Ti.It builds up a typical heterostructure that endows NiCrTi alloy with well-balanced mechanical strength and plasticity,e.g.high yield strength of 1321 MPa,compressive strength of 2470 MPa,and compressive strain of 20%.On tribocorrosion,the hard shell enriched with Ti transforms to connected protrusion and form in situ surface texture.Oxides or wear debris are trapped at the textured surface and compacted to form a stable tribofilm.Thus negative synergy between corrosion and wear is observed for NiCrTi and high tribocorrosion resistance is achieved.At a potential of+0.3 V,the tribocorrosion rate of NiCrTi is reduced by an order of magnitude to 1.87×10^(-5)mm^(3)/(Nm)in comparison to the alloy Ni20Cr.展开更多
The mechanical and wear behavior of copper-tungsten disulfide（Cu/WS_2） composites fabricated by spark plasma sintering（SPS） and hot pressing（HP） was investigated, comparatively. Results indicated that the additi...The mechanical and wear behavior of copper-tungsten disulfide（Cu/WS_2） composites fabricated by spark plasma sintering（SPS） and hot pressing（HP） was investigated, comparatively. Results indicated that the addition of lubricant WS_2 substantially reduced wear rate of the Cu matrix composites fabricated by SPS,and the optimum content of WS_2 is 20 wt% with regard to the wear behavior. However, it affected a little to the wear rate while dramatically decreased the friction coefficient of the composite fabricated by HP.This difference in friction behavior of the self-lubricating composites fabricated by the two techniques was closely related to their different mechanical properties. Severe interfacial reaction occurred during spark plasma sintering, leading to brittle phase formation at interface.展开更多
基金financially supported by the Liaoning Revitalization Talents Program(No.XLYC2203133)the Fundamental Research Funds for the Central Universities(No.N2302018)the Ningbo Yuyao City Science and Technology Plan Project(No.2023J03010010).
文摘Nickel-based alloys applied in marine environments often face multiple challenges of stress,corrosion and wear.In this work,heterostructured NiCrTi alloy was prepared by spark plasma sintering coarse Ni20Cr and ultrafine Ti powders.Apart that some are dissolved into the nickel alloy,Ti powders react in situ with Ni20Cr during sintering to form hard intermetallic Ni_(3)Ti.It builds up a typical heterostructure that endows NiCrTi alloy with well-balanced mechanical strength and plasticity,e.g.high yield strength of 1321 MPa,compressive strength of 2470 MPa,and compressive strain of 20%.On tribocorrosion,the hard shell enriched with Ti transforms to connected protrusion and form in situ surface texture.Oxides or wear debris are trapped at the textured surface and compacted to form a stable tribofilm.Thus negative synergy between corrosion and wear is observed for NiCrTi and high tribocorrosion resistance is achieved.At a potential of+0.3 V,the tribocorrosion rate of NiCrTi is reduced by an order of magnitude to 1.87×10^(-5)mm^(3)/(Nm)in comparison to the alloy Ni20Cr.
基金supported by the National Natural Science Foundation of China (No. 51471177)the Youth Innovation PromotionAssociation CAS (No. 2016178)the Fundamental Research Funds for the Central Universities (No. N160205001)
文摘The mechanical and wear behavior of copper-tungsten disulfide（Cu/WS_2） composites fabricated by spark plasma sintering（SPS） and hot pressing（HP） was investigated, comparatively. Results indicated that the addition of lubricant WS_2 substantially reduced wear rate of the Cu matrix composites fabricated by SPS,and the optimum content of WS_2 is 20 wt% with regard to the wear behavior. However, it affected a little to the wear rate while dramatically decreased the friction coefficient of the composite fabricated by HP.This difference in friction behavior of the self-lubricating composites fabricated by the two techniques was closely related to their different mechanical properties. Severe interfacial reaction occurred during spark plasma sintering, leading to brittle phase formation at interface.
