This studyfocusesonthehightemperaturetribologicalbehaviouroftheboridelayersgeneratedon4140
steel bypackboridingprocess.Boridingat750and800 1C resultedinasinglephase(Fe2B) boridelayer,
while adualphase(Fe2BþFeB) boridelayerwasdevelopedat850and900 1C. Slidingweartests
conducted byrubbinganaluminaballrevealedthatsingleanddual-phaseboridelayersexhibitedalmost
similar tribologicalperformancesandsuperiorwearresistancesatroomtemperature.Withincreasing
testing temperature,boridelayersexhibiteddifferentwearbehavioursdependingontheirphase
structure sothat,dualphaseboridelayeryieldedbetterwearresistancethansinglephaseboridelayer,
especially atthetestingtemperature of 300 1C.