论文部分内容阅读
采用SEM场发射扫描电镜与EDS能谱分析、光学显微镜和拉伸实验机对含硼460B用钢时效行为进行了研究。结果表明:含硼460B用钢经时效后,其屈服强度降低了30~60 MPa,抗拉强度最高降低30 MPa,力学性能合格试样的淬透层深度要高于不合格试样12.1μm,且其晶粒尺寸较不合格试样更为细小;硼的含量降至0.0015%~0.0018%,时效后其屈服强度降低10~25 MPa;屈服强度降低的主要原因是余热处理后过饱和的硼化物从固溶体中缓慢析出失去了对晶界及位错的有效钉扎以及自由氮在钢中脱溶且形成了对钢材有害的BN颗粒,使钢中的氮含量减少。
SEM field emission scanning electron microscopy and EDS EDS, optical microscopy and tensile testing machine for boron 460B steel used in the aging behavior. The results show that after aging, the yield strength of boron-containing 460B steel decreases by 30-60 MPa and the tensile strength decreases by 30 MPa. The depth of hardened layer of the qualified mechanical specimen is higher than that of the unqualified specimen by 12.1 μm, And its grain size is smaller than that of the unqualified sample. The content of boron is reduced to 0.0015% -0.0018%, and the yield strength is reduced by 10-25 MPa after aging. The main reason for the decrease of yield strength is that the supersaturated boron Slow precipitation of the compounds from the solid solution loses effective pinning of the grain boundaries and dislocations and free nitrogen desolvables in the steel and forms BN particles that are detrimental to the steel, reducing the nitrogen content in the steel.