Cu—Cr—Zr合金强化机理电子理论研究

通过自编软件建立了Cu合金液体、位错、晶界等原子集团模型，采用递归法计算了Cu合金电子结构。研究表明：Y在晶粒、表面、液体的环境敏感镶嵌能依次降低，Y从晶粒内向晶粒表面、液体Cu中扩散。扩散过程中Y原子填补在Cu晶粒表面缺陷处，阻碍Cu原子结晶，同时进入液体中的Y在晶粒周围形成含有高浓度Y的薄层，使晶粒生长受阻，晶粒细化。Sn向位错扩散，抑制Cr的沉淀析出，并能钉扎位错的攀移运动，推迟回复和再结晶。S在晶界偏析，使晶界结合强度降低。偏聚在晶界的S可将合金中的Zr吸附到晶界，使晶界得到强化。Cu晶粒、晶界与位错处的费米能级不同，电子在这些区域之间发生偏移，使合金内产生微电场。微电场对电子产生散射作用，使合金电阻增大。

The Electronic Theory Study on Strengthening Mechanism of Cu-Cr-Zr Alloy

The atomic cluster model of liquid Cu, dislocation, grain boundary were founded with self-programming software. The electronic structure of Cu-Cr-Zr alloy was calculated with recursion method. The research shows that the environment sensitive embedding energy of Y sequence decrease with in grain, at surface and in liquid Cu. Y atoms can diffuse from Cu grains to surface and liquid Cu, and fill in the defect at the surface of growing Cu grain, which hinder the crystallization of Cu atoms. At the same time, the film with high density Y was formed around the grain with the Y diffuse into the liquid. This makes the grain growing hindered and leads to the grain refined. Sn can diffuse to dislocation and suppress the precipitation of Cr, Sn can fix the climb motion of dislocation, retard the reflex and recrystallization. S reduce the bond strength of grain boundary as it segregate at the grain boundary. S segregating at the grain boundary pull Zr atoms moving to grain boundary, make the grain boundary becoming strengthen. Because the electronic deflect among grain boundary, dislocation and grains of Cu due to the different fermi level, the micro-electric field is created in alloy. The micro-electric field can scatter the electron, it make the electric resistance increase.