GH690合金的氢致脆性行为研究  

Hydrogen Embrittlement Behavior of GH690 Alloy

作　　者：王富强[1] 王磊[1] 刘杨[1] 王朋[1] 封辉[1] 

机构地区：[1]东北大学材料各向异性与织构教育部重点实验室,辽宁沈阳110004

出　　处：《郑州大学学报（工学版）》2009年第1期34-38,共5页Journal of Zhengzhou University（Engineering Science）

基　　金：国家"973"计划资助项目(2006CB605005)

摘　　要：采用高温高压气相热充氢方法,将氢导入GH690镍基高温合金,其浓度达38.1 mg/kg.对未充氢和充氢试样以相同的应变速率进行室温拉伸试验,通过比较两种条件下GH690合金的拉伸变形行为,考察氢对GH690合金脆化行为的影响.结果表明,氢对GH690合金的屈服强度没有明显的影响,但充氢试样的屈服台阶消失,而且合金的抗拉强度和断裂延伸率明显降低.断口分析发现未充氢试样以延性韧窝断裂为主要特征,而充氢试样则表现出脆性沿晶断裂.GH690合金在拉伸变形时,氢易以Cottrell气团的形式跟随可动位错迁移至晶界,随着塑性变形的进行,位错在晶界处积聚,导致氢富集于晶界.晶界处氢的富集降低了合金的晶界结合强度,使得微裂纹易在晶界处萌生,导致沿晶断裂的发生.Hydrogen was transported into GH690 nickel-base superalloy by high-pressure thermal precharged methodology.The tensile testing of uncharged and H-precharged specimens was conducted with the same strain rate at room temperature.The H embrittlement behavior was evaluated by comparing the H-induced ductility losses of two kinds of specimens.The results show that H has little effect on the yielding strength of the alloy,but the yielding point of precharged one disappears.H has an obvious effect on the ultimate ...

关 键 词：GH690合金 氢 氢脆 位错 

分 类 号：TG132.32[一般工业技术—材料科学与工程]