中文摘要：

为解决在水下爆炸成形制造方形连铸结晶器铜管时，由于铜管角部成形滞后直边贴膜，直边对角部形成挤压，造成角部铜管容易贴合不紧密而产生“隆起”的问题，提出一种角部炸药先行起爆的水下爆炸成形方法, 并借助有限元模拟方法对不同起爆方案设计进行分析。结果表明：角部炸药先行起爆10，15和20μs时，可以消除方形连铸结晶器角部铜管的“隆起”，成形效果较理想，与先爆20μs的实际爆炸成形试验结果相符；同时，还可大大降低爆炸载荷对芯模角部的冲击，有利于在实际生产中提高芯模使用寿命，降低生产成本。依据疲劳寿命估算理论，先爆10μs时，效果最优，是同步起爆疲劳寿命的19倍。角部炸药先行起爆的水下爆炸成形方法为方形连铸结晶器铜管的生产提供了一种新加工技术。

英文摘要：

In order to solve the apophysis which is shaped for the reason that the corner of copper tube is squeezed by straight flange and not fitting close for the corner forming of copper tube lagging the straight flange fitting when explosive forming process of square continuous casting crystallizer copper tube is done under water, a new method of explosive forming underwater with the explosive of corner in advance detonating was presented and different detonating designs were analyzed by finite element simulation method. The results show that the corner apophysis of crystallizer square copper tube can be eliminated when the explosive of corner is detonated 10,15 and 20μs earlier, which is consistent with the results of the actual experiment whose explosive in the corner is detonated 20μs earlier. Meanwhile, the impact of mould corner under the action of explosive load can be significantly reduced, which is beneficial to improve the service life, and help lower down the cost in the actual production. Based on fatigue life prediction theory, the scheme of detonating 10μs earlier has the best effect, whose fatigue life is 19 times as long as synchronous-detonating method. The proposed method of explosive forming underwater with the explosive of corner in advance blasting provides a new processing technology for square continuous casting crystallizer copper tube.