不锈钢波纹管应力腐蚀防护方法研究

不锈钢波纹管是现代工业广泛使用的金属弹性元件,长期应用实践表明,在特殊环境条件下,波纹管常常发生因应力腐蚀引发的爆炸失效事故,对环境、安全构成极大威胁。本文详细阐述了固溶处理不锈钢波纹管组形变马氏体含量分布、残余应力分布。不锈钢波纹管在加工、成型过程中,波峰波谷会发生塑性变形,一部分奥氏体组织转变为马氏体组织。试验研究结果表明,固溶处理后残余应力变为压应力,残余应力比未固溶处理波纹管的大大减小;固溶处理后形变马氏体含量较少,且分布均匀,约占0.25%;残余应力越大,马氏体含量越高,不锈钢SCC敏感性大。对固溶处理前后波纹管应力腐蚀开裂进行实验研究,研究表明,固溶处理可提高波纹管抗SCC性能;喷丸强化可提高波纹管抗SCC能力,表面硬度、强度增大,也可延长疲劳寿命。

Stress corrosion cracking protection methods study on stainless steel bellows

stainless steel bellow is metal elastic part that is widely used in modern industry.Practices have showed that,in some special environment,stress corrosion can cause bellow explode.Stress corrosion has been harmful to our environment and safety.This paper introduced marsentite percentage,residual stress distribution on stainless steel bellows after solution treatment in detail.Stainless steel bellows peaks and troughs can produce plastic deformation in process and forming,then ammonia changes in to marsentite.The testing result showed that the main residual stress were transformed to compressive stress by solution treatment,The residual stress decreased highly;the marsentite percentage drops to 0.25% after solution treatment.The more residual stress and marsentite percentage are,the more stainless steel SCC sensitivity is.Stress corrosion test were performed in 42%MgCl2 boiling solution,the testing result proves that solution treatment is a valid method to improve the anti-corrosion property of stainless steel bellows.Glass-bead-preening can also highly improve the anti-corrosion and anti-fatigue property of bellows.