混合稀土元素对HRB400钢组织及拉伸性能的影响

借助光学显微镜、扫描电镜以及电子万能试验机等手段研究了混合稀土含量对HRB400钢微观组织及力学性能的影响。结果表明，稀土含量的添加导致HRB400钢的上、下屈服点升高。并且随着稀土元素含量的增加，珠光体体积分数增多，片层间距减少，进一步提升了其抗拉强度；但是，0.045RE-HRB400钢中韧窝的数量及深度降低，使其延伸率以及断面收缩率均有所下降。 

Effects of mixed rare earth elements on microstructure and tensile properties of HRB400 steel

The effects of increasing the content of mixed rare earth on the microstructure and mechanical properties of HRB400 steel were studied by means of optical microscope, scanning electron microscope and electronic universal testing machine. The results showed that the increase of rare earth content led to the increase of the upper and lower yield points. With the increase of rare earth element content, the volume fraction of pearlite increased but the lamellar spacing decreased, which further enhanced the tensile strength. However, with rare earth content increasing, the number and depth of dimples were reduced in 0.045RE-HRB400 steel so that the elongation and reduction of the dimples were reduced.