Carbide Effects on Creep Crack Growth of Ni-Cr Austenitic Steels  

作　　者：祝苏明 朱世杰 王富岗 张俊善 

机构地区：[1]Dalian University of Technology,Dalian,116024,China [2]Institute of Metal Research,Academia Sinica,Shenyang,110015,China

出　　处：《Journal of Materials Science & Technology》1992年第6期391-396,共6页材料科学技术（英文版）

摘　　要：By controlling the carbon content of Fe-15Cr-25Ni alloys,three types of microstructures were obtained:single phase austenite (γ),γ+intergranular carbides, γ+intergranular carbides + intragranular carbides. Creep crack growth behaviour of the three alloys has been compared at 973 K and 1123 K. Intergranular carbides show higher creep crack growth resistance than intragranular carbides.Cav- ities nucleate at the triple junctions of grain bound- aries for single phase alloy,but at intergranular carbides for two-phase alloys.The precipitation of intergranular carbide not only changes the nucleation mechanism of cavities,but also inhibits the growth and coalescence of cavities.The precipi- tation of intragranular carbide obstructs the nucleation and growth of cavities furthermore.By controlling the carbon content of Fe-15Cr-25Ni alloys,three types of microstructures were obtained:single phase austenite (γ),γ+intergranular carbides, γ+intergranular carbides + intragranular carbides. Creep crack growth behaviour of the three alloys has been compared at 973 K and 1123 K. Intergranular carbides show higher creep crack growth resistance than intragranular carbides.Cav- ities nucleate at the triple junctions of grain bound- aries for single phase alloy,but at intergranular carbides for two-phase alloys.The precipitation of intergranular carbide not only changes the nucleation mechanism of cavities,but also inhibits the growth and coalescence of cavities.The precipi- tation of intragranular carbide obstructs the nucleation and growth of cavities furthermore.

关 键 词：Ni-Cr austenitic steel CREEP crack growth CARBIDE 

分 类 号：TB3-55[一般工业技术—材料科学与工程]