Preparation Of High Entropy Alloys With Multi-principle Elements By Laser Alloying

In tradition, the alloy systems is almost based on one major element, and otherelements are auxiliary to enhance the property of the alloy. After years of development,this alloy systems has tend to be perfect, a variety of alloy has been study by scholars.Therefore, the development tendency of alloy systems has been turned into break thetradition alloy systems. The theory of high entropy alloy with multi-principal elementsarises at the historic moment in such tendency. The high entropy alloy systems is basedon five major elements at least is a new theory of alloy systems and has differentproperty with the traditional alloy systems. This study using two kinds of laser（Nd: YAGlaser and semiconductor laser）, respectively, prepare FeCoCrAlCuNiMo1high entropyalloy and FeCoCrAlCuNiMoxhigh entropy alloy on2Cr13steel by laser cladding, andthen have research the microstructure and mechanical properties of FeCoCrAlCuNiMox(x=0,0.5,1） high entropy alloy systematacially.The results show that the microstructure of high entropy prepared by Nd: YAG laserand semiconductor laser are typical laser deposition organization, and compositionsegregation appeared in the dendrite and interdendritic. FeCoCrAlCuNiMo1highentropy alloy coating prepared by Nd: YAG laser were mainly composed of a simple bccsolid-solution structure(which is similar to-Fe) with no other phase.FeCoCrAlCuNiMox high entropy prepared by semiconductor laser were composed of amixed bcc and fcc solid-solution structure. Due to the effect of high entropy,theMicrohardness of FeCoCrAlCuNiMoxhigh entropy alloy made by two lasers has ascendgreatly, nearly3times larger than substrate material. The tendency of high entropy alloymade by semiconductor laser: FeCrCoNiAlCuMo0.5>FeCrCoNiAlCuMo1>FeCrCoNiAlCuMo0. The research of ball-disk friction and wear show that the wear volume ofFeCrCoNiAlCuMoxhigh entropy alloys are gradually increasing under different load,and the wear volume of FeCrCoNiAlCuMo0.5lower than that of FeCrCoNiAlCuMo0andFeCrCoNiAlCuMo1significantly. At same time, The corrosion resistance is much betterthan that of2cr13steel substrate material in the NaCl solution. All of FeCoCrAlCuNiMoxhigh entropy alloys have appeared self-passivating-areas, but it isvery narrow.