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航空发动机空心叶片的复杂内腔只能用陶瓷型芯来成形,而陶芯的脱除通常用化学腐蚀法。如硅基陶芯在碱液中脱除,氧化镁陶芯在酸液中脱除。但陶芯经高温烧结及浇注合金后,结构较致密,颗粒间结合较牢固。如脱芯工艺选择不当,对复杂薄壁陶芯很难从铸件中脱除;或者因脱芯时间过长,铸件被脱芯液腐蚀,产生过厚的界面层或晶界腐蚀而使铸件报废。因此研究脱芯工艺对生产实践颇有意义。英、美等国对此较为重视,有的成立专门小组进行研究并作了一些报导。国内在脱芯中存在问题很多,尚缺乏研究。
Aero-engine hollow blades of the complex cavity can only be formed with a ceramic core, and removal of the ceramic core is usually chemical etching method. Such as silicon-based ceramic core removed in the lye, magnesia ceramic core removed in the acid. However, the high-temperature ceramic core sintering and casting alloy, the structure is more dense, more solid combination of particles. If unsuccessful choice of de-core process, the complex thin-walled ceramic core is difficult to remove from the castings; or because the de-coking time is too long, the casting is de-cored liquid corrosion, resulting in too thick interfacial layer or grain boundary corrosion casting scrapped. Therefore, it is of great significance to study the process of debonding for the production practice. The United Kingdom, the United States and other countries attach more importance to this, some set up a special group to conduct research and made some reports. There are many problems in the process of de-core in China, but there is still a lack of research.