声束调控替代核电CV消应力热处理可行性研究

Feasibility study of ultrasonic regulation to replace nuclear CV stress-relief heat treatment

针对核电钢制安全壳(CV)消应力热处理需求进行论证,从理论上分析了声束调控替代热处理的优越性和可行性;对比分析了焊态、热处理态和声束调控态的焊件力学性能和残余应力分布。结果表明,声束调控应用可有效降低接头残余应力,平均应力消减率达24.4%,声束调控2 h的应力消减效果与热处理保温10 h的效果相当,且声束调控对接头拉伸强度、延伸率、冲击性能并无劣化影响。这说明声束调控技术可替代消应力热处理,并给出了需进一步深入研究的方向。

The requirement of stress-relief heat treatment for Nuclear Power Plant steel containment vessel(CV)is demonstrated,and the advantages and feasibility of replacing heat treatment with ultrasonic regulation are analyzed theoretically.The mechanical properties and residual stress distribution on weld state,heat treatment state and ultrasonic regulation state are compared and analyzed.The results show that the residual stress of the joint can be effectively reduced by ultrasonic,and the average stress relief rate reaches 24.4%.The stress reduction effect of ultrasonic regulation for 2 hours is similar to that of heat treatment for 10 hours.At the same time,there is no obviously deterioration in tensile strength,elongation and impact properties of the joint under ultrasonic regulation.It is considered that the ultrasonic regulation technique could replace the stress-relief heat treatment,and the direction of further research is given.