M330塑料模具镶件失效分析  

Failure Analysis of M330 Plastic Mould Steel Insert

作　　者：王生朝[1] 孙斌[1] 

机构地区：[1]湖南工业大学冶金工程学院,株洲412000

出　　处：《理化检验（物理分册）》2010年第8期525-528,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：综合分析了一种用来注塑手机屏的长方形M330塑料模具镶件过早失效的原因。利用扫描电镜对镶件的工作表面形貌及显微组织进行了分析,并测定了洛氏硬度,用纳米压痕仪对失效镶件表面微区硬度值进行了测定。结果表明:为方便镶件表面蚀刻而增加的一道回火工序使得镶件硬度降低,耐磨性下降,这是导致镶件过早失效的最主要原因;而镶件工作表面腐蚀圆坑设计的改变是导致其早期失效的另一个重要因素,新的设计使得注入的塑料在相互连通的坑内能够较为自由的流动,加剧了镶件的磨损。Premature failure of a plastic mould insert made of M330 steel for injecting cellphone was analyzed. The morphology and micmstructure of the failed insert＇s working surface were analyzed by scanning electron microscopy and Rockwell hardness was also tested. The hardness of the surface micro-areas was measured by nanoindentation. It was found that the main reason resulting in the failure was the reduction of hardness and wear resistance caused by three times of tempering among which an additional tempering was aimed to the convenience of etching process. Another main factor was the change of the working surface corroded dots design, because the new design made the insert plastic flow more freely than the old one and the abrasion was aggravated.

关 键 词：M330塑料模具钢 镶件 失效分析 纳米压痕 

分 类 号：TG76[金属学及工艺—刀具与模具]