【摘要】 镁合金热室压铸机所用坩埚在使用3～4个月后在靠近外焰的底部和侧面结合处发生严重的变形开裂,对开裂原因进行了分析。结果表明:开裂的主要原因是坩埚在使用过程中沿横截面存在温度梯度;温度过高的外表面在奥氏体化过程中产生了拉应力,同时表面存在脱碳使强度降低,最终在该拉应力的长期作用下坩埚表面开裂直至报废。更多还原

【Abstract】 After been used for 3 - 4 months, the crucible had serious crack at the joint of the bottom and side closing to the outer flame. It’s analyzed that the temperature gradient along cross section causes the crack. The outer surface’s temperature is too high, so that the stress in the process of austenization, and the surface losing carbon makes the intensity decrease, eventually, the crucible cracked.更多还原