钴基高温合金冶炼La含量的控制

The Smelting Control of La Content in Co-based Superalloy

本文就含La合金真空感应+电渣重熔双联冶炼过程中La的烧损规律进行了研究,结果显示,在真空感应熔炼过程中,精炼后期加入La,由于其活性太高,加入的La与钢液中的氧、硫等元素充分反应,所加入的La几乎烧损殆尽。在冶炼末期出钢前加入La,—方面由于合金冶炼末期,钢液中的氧含量被脱的较为充分,另一方面在加入La后及时出钢,使得加入的La没有充分的时间进行物化反应,从而在最终的钢锭中得以较好的保留。另外,随着La加入量増加,La的回收率也随之上升。本文还考察了CaF2:Al2O3、CaF2:Al2O3:CaO与CaF2:Al2O3:CaO:La2O3三个渣系下的电渣重熔中La的烧损规律:前两个渣系La的回收率在13%~19%之间,两个渣系La的烧损差别不大;加La2O3的四元渣系回收率为10%~13%,La的烧损明显较前两个渣系大。但就合金锭不同部位La的均匀性而言,加La2O3的四元渣系最好。电渣重熔过程中采用铝粉脱氧対La的回收率稍有提高,但幅度不大。

In this paper, the law of La burning during VIM+ESR smelting process in a superalloy containing La were studied. The results show that in vacuum induction melting process in the refining later added, the added La burning almost exhausted. At the end of the pre-steel tapping smelting, La can be better preserved. This paper also examines the law of the burning of La under three different electroslag remelting slag system, that quaternary slag system plus La2O3 contain the best effect. La recoveries under electroslag remelting process using aluminum deoxidation increased slightly.