合金灰铸铁玻璃模具开裂失效分析及改进措施

Analysis of Cracking Failure of Glass Mold Alloyed Gray Iron and Improvement Measures

分析了合金灰铸铁玻璃模具开裂失效的原因,从模具的铸造工艺和热处理工艺上进行了改进试验。通过采用降低合金元素和多次孕育的工艺,组织的均匀性明显提高,通过提高高温石墨化温度,增加二次石墨化保温时间,得到全铁素体基体组织,模具组织的均匀性得到极大的改善。最后指出:(1)模具组织中的网状碳化物以及退火残存的珠光体是裂纹产生的主要原因;(2)提高高温石墨化温度,增加二次石墨化保温时间,有利于得到高温下稳定的全铁素体组织,模具组织的均匀性得到极大的改善。

The reasons for the cracking and failure of glass mold alloyed gray iron were analyzed.Improvement tests were conducted on the casting process and heat treatment process of the molds.By adopting the process of reducing alloy elements and using multiple inoculations,the uniformity of the structure was significantly improved.By increasing the high-temperature graphitization temperature and increasing the holding time of secondary graphitization,a full ferrite matrix structure was obtained.The uniformity of the mold structure was greatly improved.Finally,it was pointed out:(1)The network carbides in the mold structure and the pearlite remaining after annealing were the main causes of cracks.(2)Increasing the high-temperature gra-phitization temperature and increasing the secondary graphitization holding time were conducive to obtaining stable full ferrite structure at high temperatures.The uniformity of the mold structure was greatly improved.