氮和氧含量对HCM2S钢组织和性能的影响

通过对4炉经过正火+回火热处理的HCM2S钢管进行拉伸试验,结合微观组织观察和能谱分析,研究了氮和氧含量对HCM2S钢组织和性能的影响.结果表明:当HCM2S钢中氮的质量分数大于71×10-6时会和硼元素反应生成BN夹杂物,从而使钢中"有效硼"量减少,降低钢的淬透性,最终影响组织和性能.氮含量不高于71×10-6时,氧的质量分数在14×10-6～49×10-6内变化不会对HCM2S钢组织和性能造成影响.通过在钢中加入少量Ti元素,即使氮含量较高,Ti也可以和氮发生反应生成氮化钛,从而获得全贝氏体组织和优异的力学性能.

Influence of nitrogen and oxygen contents on the microstructure and performance of HCM2S steel

The influence of nitrogen and oxygen contents on the microstructure and performance of HCM2S steel was studied by the room temperature tensile test of 4-furnace HCM2S steel tubes after being normalized and tempered,microstructure observation,and energy dispersive spectrum analysis.The results show that when the mass fraction of nitrogen is larger than 71×10-6,the depletion of useful boron and the reduction of harden ability will take place,which would affect the microstructure and performance of the steel.The fluctuation of the mass fraction of oxygen in the range of 16×10-6 to 49×10-6 has no influence on the microstructure and performance of HCM2S steel,when the nitrogen content is no more than 71×10-6.Addition of a little titanium will cause the reaction with nitrogen,save the content of useful boron,and obtain the bainite structure and excellent mechanical properties even with higher nitrogen content.