Incoloy 800波纹管膨胀节开裂失效分析

Failure Analysis of Cracking of Expansion Joint of Incoloy 800 Bellows

金属波纹管膨胀节具有热补偿功能,应用越来越广,同时其失效开裂问题也日益显现。为此,从宏观形貌、化学成分、金相显微组织、SEM微观形貌方面,对开裂的Incoloy 800波纹管膨胀节进行了分析。结果表明,波纹管膨胀节开裂的原因是高轴向拉应力条件下的材料失稳破裂,并提出了相应的改进措施。

The causes leading to cracking of the expansion joints of Incoloy 800 bellows were investigated in relation to analyses of macromor-phology,chemical composition,metallographic structure,and micromorphology of fractured surfaces by scanning electron mi-croscopy.The measures for modification were suggested.Results show that the cracking of the expansion joints of lncoloy 800 bel-lows may be attributed to destabilization rupture caused by high axial tensile stress.