超低温温度场中Cu-Zr-Cr合金显微结构转变规律

The research on the change law of Cu-Zr-Cr alloy's microstructure in cryogenic temperature field

研究超低温温度场中Cu Zr Cr合金基体组织(α固溶体)形成孪晶结构并析出弥散的Cu3Zr和Cr2Zr金属间化合物及基体组织微细化的过程。孪晶可以在93K低温下形成和扩展。析出Cu3Zr和Cr2Zr强化相,细化了基体组织。试验表明:以上组织结构的变化,提高了合金抗高温塑性变形能力,减轻了高温焊接时粘焊现象的发生,电极的耐磨性明显提高。

:In this paper,Cu-Zr-Cr alloy's matrix tissue (α solid solution) forming twin structure,separating disperse intermetallics (Cu_3Zr and Cr_2Zr) and the process of matrix tissue being fine grained in cryogenic temperature field were researched.The formation of twin structure depends on the slip of stacking fault to nucleate and gradually extend.The needed stress of developing twin is less than the needed stress of slip,the Burgers vector of twinning dislocation is less than the normal dislocation,so the Peierls-Nabarro force of twinning dislocation is smaller too.The twin may form and extend under 93K condition.The experiment indicates that the changes of structure above improve the alloy's ability of resistance to plastic deformation in high temperature,lighten the phenomenon of cementation by welding in high temperature welding.The abrasion resistance of electric pole improves obviously.