控制棒驱动机构钩爪Stellite6合金熔模铸件的制造工艺研究

Study on Manufacturing Process of Stellite6 Alloy Investment Castings of Control Rod Drive Mechanism Latch

在三代非能动压水堆核电设备控制棒驱动机构中,首次使用了Stellite6合金作为钩爪铸件材料。该材料是一种可耐各类腐蚀以及高温氧化的硬质合金,具有很好的耐磨损性能。由于钴基合金铸件在浇注冷却过程中极易开裂,因此在冷却过程中应采用缓冷的工艺,以减少铸件的内应力。考虑到Stellite6合金的这些特性和及其使用条件,选取了两种工艺方案进行研制。通过对两种工艺方案结果的分析,获得了较好的Stellite6合金铸件的制造工艺。

Stellite6 alloy is firstly used for latch material in Generation-Ⅲ passive PWR control rod drive mechanism. This kind of material is famous for its good anti-corrosion property, good anti-high temperature oxidation and good anti-abrasive property. Since the cobalt matrix alloy is most likely to crack when cooling after pouring, the cooling process should use the slowly cooling method to decrease the inner stress of the castings. Thinking over the characteristics and the working conditions of Stellite6 alloy, two kinds of manufacturing process were selected. By analyzing these two kinds of process, a better manufacturing process of Stellite6 alloy was obtained.