Abstract
Initially defined high entropy alloys(HEAs)usually exhibit a single-phase solid-solution structure.However,two and/or more types of phases in HEAs pos-sibly induce the desired microstructure features,which contribute to improving the wear properties of HEAs.Here,we prepare a series of(AlCoCrFeNi)100-xHfx(x=0,2,4 and 6;at％)HEAs and concern their phase compositions,microstructures and wear properties.Hf leads to the for-mation of(Ni,Co)2Hf-type Laves phase and tailors the microstructure from a body-centered cubic(BCC)single-phase structure to a hypoeutectic structure.An increased hardness from～HV 512.3 to～HV 734.1 is due to solid-solution strengthening,grain refinement strengthen-ing and precipitated phase strengthening.And a few oxides(Al2O3+Cr2O3)caused by the wear heating contribute to an 85.5％decrease in wear rate of the HEA system from 6.71 × 10-5 to 0.97 × 10-5 m3·N-1·m-1.In addition,Hf addition changes the wear mechanism from abrasive wear,mild oxidative wear and adhesive wear to oxidative wear and adhesive wear.
基金项目
National Natural Science Foundation of China(51825401)
Postdoctoral Foundation of Heilongjiang Province(LBH-Z19154)
National Natural Science Foundation of Heilongjiang Province(LH2020E031)
Interdisciplinary Research Foundation of HIT()
NETL
NSTL
万方数据