论文部分内容阅读
我国焊接冷裂纹的研究现状焊接冷裂纹是焊接接头冷却到温度较低的条件下产生的一种裂纹,在低合金高强度钢焊接结构的焊接裂纹中,占有较大的比例。多数的焊接冷裂纹,其萌生与扩展有时间延迟的特性,称为延迟裂纹,这给裂纹的检测与防止,带来较大的复杂性,也给产品的安全使用带来很大的危害性。近十年来,我国许多大型的低合金高强度钢与超高强度钢的焊接结构,由于存在焊接冷裂纹,致使有的产品返修、降级使用或报废,有的产品则因没有检测到裂纹的存在,致使产品在运行中造成低应力破坏。例如球形压力容
Research status of welding cold crack in China Welding cold crack is a kind of crack produced when the welded joint is cooled down to a lower temperature, occupying a larger proportion in the welding crack of low alloy high strength steel welded structure. Most of the cold welding cracks, the initiation and extension of its time delay characteristics, known as the delayed crack, which gives the detection and prevention of cracks, bringing greater complexity, but also to the safety of the use of the product bring great harm . In recent ten years, many large-scale low-alloy high-strength steel and ultra-high-strength steel welded structures in our country have some products being repaired, downgraded or scrapped due to the existence of cold welding cracks. Some products have no crack detected , Resulting in the operation of the product caused by low stress damage. For example spherical pressure capacity