Hydrogen,asatemporaryelementintitaniumalloys,isverygoodincontrollingmicrostructure.ThemicrostructureandphasetransformationofTi6A14ValloyareaffectedbytheamountofTiH,addedintothemeltofTi6A14Valloyduringtheinductionskullmelting（ISM）process.Thisprocess,calledmelthydrogenation,wasstudiedinthispaperthroughtheuseofopticalmicroscopy,scanningelectronmicroscopy（SEM）andtransmissionelectronmicroscopy（TEM）.Theresultsareasfollows:aftermelthydrogenation,boththesolidificationmacrostructureandmicrostructureofTi6A14Valloyarerefined;theαphaseprecipitatesinalamellarformwiththeresidualβphasefromthegrainboundaries;δ-hydridesprecipitateduringthesolidificationprocessasaresultoftheexistenceofhydrogen.TheSphasewithanF.C.C.structurecanbeobservedbyTEMintheαphaselaminaeofspecimenswith1.25%TiH2.Inaddition,thedependenceofthemicrohardnessofspecimensontheweightpercentageofTiH,addedtothemeltduringtheISMprocesswasalsostudied.
