水下连接器锻件低温冲击韧性不合格原因分析及工艺改进措施研究

Analysis of Unqualified Low-Temperature Impact Toughness of Underwater Connector Forgings and Research on Process Improvement Measures

针对某深水开发项目用水下连接器锻件低温冲击韧性值过低的问题,采用化学成分分析、金相分析、微观分析等技术手段,并结合该锻件的结构与热处理工艺,对冲击韧性值偏低的试件进行全面分析,找出低温冲击韧性不合格的原因。结果表明,该锻件冲击韧性值过低的部位均位于结构中厚度较大位置内芯部位,由于厚度过大,在热处理过程中,锻件内芯部位温度控制不佳,导致晶界温度过热。对热处理工艺进行改进,有效改善了内芯部位的散热情况,最终使锻件低温冲击韧性合格。

Aiming at the problem of low impact toughness of underwater connector forgings in a deep water development project,through the use of chemical composition analysis,metallographic analysis,micro analysis and other technical means,combined with the structure and heat treatment process of the forgings,a comprehensive analysis of the specimens with low impact toughness was carried out to find out the causes of unqualified lowtemperature impact toughness.The results showed that the parts with too low impact toughness were located in the inner core part of the structure with a larger thickness.Due to the excessive thickness,the temperature of the inner core part of the forging was not well controlled during the heat treatment process,which led to overheating of the grain boundary temperature.After the heat treatment process was improved,the heat dissipation of the inner core was effectively improved,and finally the low-temperature impact toughness of the forging was qualified.