中、低强度结构钢,在低温条件下,都有一个脆性趋势,对此,人们不是一开始就认识它的意义,而是在出现了一系列的事故后,经过大量的研究才了解到在低温工作条件下结构钢脆性的问题。尤其以二次世界大战前后出现的桥梁、船舶、贮罐等的脆性破坏事故,促使人们用各种各样试验方法对它进行研究,其中有V却贝冲击试验、罗伯逊止裂试验、落锤试验、宽板试验、双重拉伸试验、深缺口试验等,这中间大部分是属于研究性质的,而其中有一些已列入了各种规范或某些规范中,如V却贝冲击试验和落锤试验,V却贝冲击是大家已熟知的,落锤试验在一些国家里已列入了船规和低温压力容器规范中,在美国作为材 Medium and low-strength structural steels have a tendency to be brittle at low temperatures, for which people do not recognize its significance from the very beginning, but after a series of accidents, it is understood that after a series of accidents, Structural Steel Brittleness at Low Temperatures. In particular, the brittle failure of bridges, ships and storage tanks that occurred before and after the Second World War prompted people to study it with various test methods, including the V Charpy impact test, the Robertson stop test, the drop hammer Test, wide panel test, double tensile test, deep notch test, etc., most of which belong to the research nature, and some of them have been included in a variety of norms or some norms, such as V Charpy impact test and Drop hammer test, V Charpy impact is well known to everyone, drop hammer test in some countries have been included in the ship gauge and cryogenic pressure vessel code, in the United States as a timber