高强度螺栓延迟开裂组织敏感性的研究

Research of Delaying Structural Fracture Sensibility of High Strength Bolt

延迟开裂是高强度螺栓等汽车零件重要失效形式之一,具有广泛性和多发性,有效地控制和防范延迟开裂的发生,在工程上有着非常重要的意义和技术指导性。通过对不同材料、不同热处理工艺、不同应力下高强度螺栓延迟开裂的敏感性试验,得出马氏体及其回火组织有较强敏感性的结论,同时提出了晶界滑移和低温蠕变的机理。

Delaying fracture is one of most important failure forms of high strength automotive bolts,which has the features of universality and frequent occurrence.It has an important significance and technology direction in engineering to control and prevent effectively the fracture.The conclusion that martensite and its tempering structure have more sensibility is obtained through sensibility test of high strength bolt delayed fracture under the conditions of different materials,different heat treatment processes and different stresses,and put forward the mechanism of grain boundary migration and low temperature creep.