Nb含量对改良型GCr15组织与性能的影响

Effects of Nb Content on Microstructure and Properties of Modified GCr15

通过OM、SEM、拉伸以及硬度试验,研究了不同Nb含量对于改良型GCr15组织与性能的影响。结果表明,淬回火后的GCr15试验钢组织均为回火马氏体、少量残余奥氏体以及碳化物,添加Nb后奥氏体晶粒细化,碳化物类型发生改变,出现NbC析出相。当Nb含量为0.04%时,钢的抗拉强度最高,达到了1249.81 MPa;当Nb含量为0.08%时,钢的硬度(HRC)最高,为61.2。

The effects of different Nb contents on structure and properties of modified GCr15 were investiagted by OM,SEM,tensile and hardness tests.The results indicate that microstructure of the GCr15 experimental steel after quenching and tempering is composed of tempered martensite,a small amount of retained austenite and carbide.After the addition of Nb element,the austenite grain is refined with convention of the type of carbides,and NbC precipitated phase appears.When the content of Nb is 0.04%,the tensile strength of steel is the highest,reaching 1249.81 MPa.When the Nb content is 0.08%,the hardness of the steel reach maxinum value,which is 61.2 HRC.