热处理对油井管的微观组织和性能的影响

Effect of heat treatment on microstructure and properties of oil well steel pipes

利用OM、TEM及电化学试验等分析手段,研究了热处理对油井管的微观组织、析出相、力学性能和耐蚀性能的影响关系。结果表明:热处理后油井管的显微组织为回火索氏体,随着热处理次数的增加,晶粒和析出相尺寸都是先变小后长大,强度和耐蚀性能先升高后降低,经过两次热处理的油井管晶粒细化,微观组织均匀,析出相细小弥散,使得油井管的屈服强度和抗拉强度最高,极化电阻最大,耐蚀性能最好。

Effects of heat treatment on microstructure,precipitated phase,mechanical properties and corrosion resistance of oil well steel pipes were studied by OM,TEM and electrochemical methods.The results show that the microstructure of the quenched and tempered oil well steel pipes is composed of tempered sorbite.With the increase of heat treatment times,both the grain size and the precipitated phase size decrease first then increase,the strength and corrosion resistance increase first then decrease.After two tempering treatments,the grain of oil well steel pipe is refined,the microstructure is uniform,and the precipitated phase is fine and dispersed,which make that the oil well steel pipe has the highest yield strength and tensile strength,the largest polarization resistance and the best corrosion resistance.