前言在用低合金高强钢制造船体结构时,如何防止焊接裂缝是一个重要课题。在生产实践中,大家知道,焊接接头的刚性越大越容易产生裂缝;用以防止焊接裂缝的预热温度同接头的刚性大小也有关系。但在过去,对焊接接头的刚性只有定性的概念,而缺少定量的方法,因此在生产实践中,迫切要求解决如下问题:对实际的焊接接头的刚性进行定量评定,以确定在不同刚性水平下某钢种产生冷裂缝的倾向。所谓“拘束度”,就是具体用来评定焊接接头刚性大小的一个力学参量,它对定量研究焊 Preface How to prevent welding cracks is an important issue in the manufacture of hull structures made of low alloy high strength steel. In production practice, we all know that the greater the rigidity of welded joints, the more likely to produce cracks; to prevent the preheating temperature of welding cracks with the size of the joints also have a relationship. In the past, however, there was only a qualitative concept of the rigidity of a welded joint, but a lack of a quantitative method. Therefore, in practice, there is an urgent need to solve the problem of quantitatively evaluating the rigidity of an actual welded joint to determine the rigidity at different levels of rigidity A steel tend to produce cold cracks. The so-called “restraint” is a specific mechanical parameters used to assess the stiffness of the welded joints, it quantitative study of welding