摘要
对一种新的-40—-50℃下使用的低温乙烯球罐用钢14MnSiNbRE的手工电弧焊和热模拟试样,采用电算示波冲击试验,测定了HAZ在不同温度下的临界裂纹张开位移COD和-40℃时的扩展阻力曲线,将冲击功分解成裂纹萌生功和裂纹扩展功,用回归分析法推断出断裂韧性COD和冲击功中的裂纹扩展功部分在物理意义上有良好的相关性,并初步探讨了焊接与热模拟对钢韧性的不同影响。
As a new material for spherical pressure vessels operated at the range from - 40℃ to- 50℃, the steel 14MnSiNbRE was investigated for its low-temperature toughness in heat effected zone (HAZ). Tests were carried out mainly by means of a thermal simulation system Gleeble-1500 and Charpy-V electronic measuring impact testing machine with the method of crack opening displacement (COD), using both simulated and hand-operated arc-welded specimens. It was found that COD correlates well with the crack propagation energy shown by the Charpy-V impact test results. Different effects of the actual welding operation and of thermal simulation on the toughness of steel are also discussed.
关键词
合金钢
压力容器钢
低温韧性
HAZ
pressure vessel steel, heat affected zone, low temperature toughness, crack opening displacement, correlativity.
