An equiatomic CoCrFeNiMn High Entropy Alloy(HEA)was in-situ deposited by the powder-bed arc ad-ditive manufacturing(PBAAM)process for the first time.Comparative research was conducted on the evolution of phase,crystallographic orientation,dislocation morphology,precipitation,and mechanical performance with the accumulation of inter-layer remelting times.The experimental outcomes mani-fested that the PBAAMed CoCrFeNiMn HEA consists of a stable solid-solution FCC structure,with de-creased lattice parameter but slightly increased(full width at half maximum)FWHM as the accumulation of the inter-layer remelting.The{001}<100>cube texture with a weakened texture intensity was de-tected with an increment of inter-layer remelting frequency from once to 5 times,yet it was transformed into{011}<100>Goss texture with a further increase to 7 times.Additionally,the mean grain diameter distinctly decreased,while the volume fraction of(low angle grain boundaries)LAGBs and dislocation density remarkably added up as the accumulated inter-layer remelts.Predominant cellular substructure generated in all process conditions and could be easily differentiated by elemental segregation.Both theσ and M23C6 Cr-rich precipitates in nano-scale and submicron MnS precipitate were detected on the grain boundaries of the PBAAMed deposited components,with a rather sparse distribution.Speaking of mechanical performance,the YS,UTS,and hardening rate are generally increased while the UE is grad-ually decreased as increased inter-layer remelting times.The studied PBAAMed CoCrFeNiMn HEA pos-sesses comparable mechanical performances with the counterparts of laser-deposited and as-cast ones.The strengthening mechanisms of the studied material are predominantly the grain boundary strength-ening and dislocation strengthening.This investigation would be a valuable resource in the research field of fabricating HEA alloys with acceptable microstructure and properties using the PBAAM method.

Jun Wang;Yao Lu;Fanghui Jia;Wenzhen Xia;Fei Lin;Jian Han;Ruichao Wang;Zengxi Pan;Huijun Li;Zhengvi Jiang

School of Mechanical Materials,Mechatronic and Biomedical Engineering,University of Wollongong,Wollongong,New South Wales 2522,Australia;School of Metallurgical Engineering,Anhui University of Technology,Maanshan 243000,China;Department of Structure and Nano-/Micromechanics of Materials,Max-Planck-Institut für Eisenforschung GmbH,Düsseldorf 40237,Germany;Faculty of Intelligent Manufacturing,Wuyi University,Guangdong 529020,China

材料科学技术（英文版）

[1]Jun Wang;Yao Lu;Fanghui Jia;Wenzhen Xia;Fei Lin;Jian Han;Ruichao Wang;Zengxi Pan;Huijun Li;Zhengvi Jiang-.Effects of inter-layer remelting frequency on the microstructure evolution and mechanical properties of equimolar CoCrFeNiMn high entropy alloys during in-situ powder-bed arc additive manufacturing(PBAAM)process)[J].材料科学技术（英文版）,2022(18):90-104

PBAAM,ditive,fested,PBAAMed,remelts

Effects,inter,layer,remelting,frequency,microstructure,evolution,mechanical,properties,equimolar,CoCrFeNiMn,high,entropy,alloys,during,situ,powder,bed,additive,manufacturing,process,An,equiatomic,High,Entropy,Alloy,HEA,was,deposited,by,first,Comparative,research,conducted,phase,crystallographic,orientation,dislocation,morphology,precipitation,accumulation,times,experimental,outcomes,mani,that,consists,stable,solid,solution,FCC,lattice,parameter,slightly,increased,full,width,half,maximum,FWHM,cube,texture,weakened,intensity,increment,from,once,yet,transformed,into,Goss,further,Additionally,mean,grain,diameter,distinctly,decreased,while,volume,fraction,low,angle,boundaries,LAGBs,density,remarkably,added,up,accumulated,Predominant,cellular,substructure,generated,conditions,could,easily,differentiated,elemental,segregation,Both,M23C6,rich,precipitates,nano,scale,submicron,MnS,were,detected,components,rather,sparse,distribution,Speaking,YS,UTS,hardening,are,generally,UE,grad,ually,studied,sesses,comparable,performances,counterparts,laser,cast,ones,strengthening,mechanisms,material,predominantly,boundary,This,investigation,would,valuable,resource,field,fabricating,acceptable,using,method

0.525124