钼基合金单晶的生产方法

PROCESSING OF MOLYBDENUM BASED SINGLE CRYSTALS

利用电子束区域熔炼方法研究了钼基合金（ＭｏＮｂ、ＭｏＨｆ、ＭｏＨｆＣ和ＭｏＮｂＨｆＣ）单晶的生产工艺过程。在ＭｏＮｂ合金长大时，没有遇到什么困难。但是，形成ＭｏＨｆ合金单晶的临界扫描速度取决于铪含量。为了避免凝固过程中过分的溶质偏析，ＭｏＨｆ合金的扫描速度必须高于２２．４ｍｍ／ｈ。业已发现，ＭｏＨｆ合金中的最佳铪含量为２．８％。

A study of the preparation of Mo based alloy single crystals (Mo Nb,Mo Hf,Mo Hf C和Mo Nb Hf C) was conducted using an etectron beam zone melting method.No difficulty was encountered when growing the Mo Nb alloys.However,for the Mo Hf alloys,the critical scan rate for single crystal formation was found to depend on Hf content.In order to avoid excessive solute segregation during solidification,the scan rate for Mo Hf alloys must be higher than 22.4 mm/h.The optimum Hf content in Mo Hf alloys was found to be 2.8%.