文章信息/Info

Title:

The development of single crystals of high-purity refractory metals and alloys

作者:

李來平; 胡忠武; 殷 濤; 張 文; 高選喬; 郭林江; 任廣鵬; 張平祥; 李中奎

西北有色金屬研究院，陜西 西安 710016

Author(s):

LI Laiping;  HU Zhongwu;  YIN Tao;  ZHANG Wen;  GAO Xuanqiao;  GUO Linjiang;  REN Guangpeng;  ZHANG Pingxiang;  LI Zhongkui

Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China

關鍵詞:

 ; 難熔金屬合金單晶; 電子束懸浮區域熔煉; 等離子弧熔煉; 固溶強化

DOI:

10.7502/j.issn.1674-3962.2014.09.04

文獻標志碼:

A

摘要:

本文主要介紹了難熔金屬及其合金單晶的制備技術，對電子書懸浮區域熔煉技術和等離子弧熔煉技術進行了比較。電子束懸浮區域熔煉法溫度梯度易于控制、材料不受坩堝材料污染，但熔體表面張力對活性雜質和溫度梯度敏感性高，所能制備的高純難熔金屬及其單晶材料尺寸規格受到很大限制，且材料內部位錯密度較高。等離子弧熔煉法加熱源能量密度高，原料規格形式多樣，可制備單晶棒材、板材、管材及其他特定形狀的單晶鑄件，可最大程度地去除雜質元素（尤其是碳元素），但設備系統復雜，單晶材料位錯密度大。本文還討論了單晶材料發展現狀，通過固溶強化可進一步提高材料的高溫性能及其穩定性。單晶管材的制備也是一個發展方向。此外論文還對單晶材料制備技術和發展前景提出了一些建議。

Abstract:

In this letter, we report the processing technology of single crystals of high-purity refractory metals and alloys, and compare the electron-beam floating zone melting(EBFZM) with the plasma arc melting(PAM). By EBFZM, the temperature gradient could be controlled easily and the contamination by crucible materials is avoided, whereas the surface tension of melt is sensitive to the active impurity content and the temperature gradient. Furthermore, the dimensions of high-purity refractory metals and the monocrystalline materials are severely limited and the dislocation density in the materials is relatively high. PAM has the advantages such as high energy density of heating and various specifications of raw materials, by which the single crystal castings could be processed in the shape of rod, plate, tube and other specific shapes. Meanwhile, the impurity elements (especially carbon) are maximally removed. However, the equipment is complex and the dislocation density is high. We also discuss the status of development for single crystal materials, such as improving the resistance to high temperature and stablilty by solid-solution strengthening. The processing of single crystal tubes is also an interesting topic. We make some suggestions on the processing technology and developing prospect for single crystals of refractory metals and alloys.