The Study on Plasma Boriding of H13 Steel at Low Temperature Assisted by Surface Nanocrystallization Technology  

作　　者：Yang Haopeng Wu Xiaochun Wu Tianrong 

机构地区：[1]Shanghai Univ, Sch Mat Sci & Engn, Shanghai 200072, Peoples R China

出　　处：《稀有金属材料与工程》2012年第S1期309-314,共6页Rare Metal Materials and Engineering

基　　金：Supported by Shanghai Leading Academic Discipline Project(S30107)

摘　　要：Plasma boriding treatment was carried out at low temperature for the hot work die steel H13 assisted by surface nanocrystallization technology in this paper.At the same time,the thermal fatigue property of it was investigated through thermal fatigue testing with 3000 continuous cycles from room temperature to 700℃.The changes of structure and grain size in surface layer were characterized by high-resolution transmission electron microscopy(HRTEM).After plasma boriding at 580℃ for 4 h,the phase composition,morphology and in-situ nanomechanical property of boride layer were investigated by X-ray diffraction spectroscopy(XRD),scanning electron microscope(SEM),nanoindentation test,respectively.The results show that the boride layer with about thickness of 5μm is composed with two phases of Fe2B and FeB.The nanohardness of boride layer is as high as 21 GPa.Furthermore,thermal fatigue testing shows that the boride layer with excellent oxidation resistance and mechanical strength at elevated temperatures could effectively delay the crack initiation and impede the crack propagation.Therefore,the thermal fatigue property of H13 can be remarkably improved.Plasma boriding treatment was carried out at low temperature for the hot work die steel H13 assisted by surface nanocrystallization technology in this paper.At the same time,the thermal fatigue property of it was investigated through thermal fatigue testing with 3000 continuous cycles from room temperature to 700℃.The changes of structure and grain size in surface layer were characterized by high-resolution transmission electron microscopy(HRTEM).After plasma boriding at 580℃ for 4 h,the phase composition,morphology and in-situ nanomechanical property of boride layer were investigated by X-ray diffraction spectroscopy(XRD),scanning electron microscope(SEM),nanoindentation test,respectively.The results show that the boride layer with about thickness of 5μm is composed with two phases of Fe2B and FeB.The nanohardness of boride layer is as high as 21 GPa.Furthermore,thermal fatigue testing shows that the boride layer with excellent oxidation resistance and mechanical strength at elevated temperatures could effectively delay the crack initiation and impede the crack propagation.Therefore,the thermal fatigue property of H13 can be remarkably improved.

关 键 词：HOT work DIE steel H13 surface NANOCRYSTALLIZATION PLASMA BORIDING treatment at low temperature 

分 类 号：TG146.4[一般工业技术—材料科学与工程]