Cr对Mg-Zn-Al-Cu合金沉淀析出过程的影响  

Effects of Cr on Precipitation Strengthening Process of Mg-Zn-Al-Cu Alloy

作　　者：孙旭光[1] 董允[1] 林晓娉[1] 苏蕙[1] 李媛媛[1] 

机构地区：[1]河北工业大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2010年第3期279-282,共4页Special Casting & Nonferrous Alloys

摘　　要：通过SEM、X射线衍射等试验手段,研究了合金元素Cr对Mg-10Zn-2Al-1Cu镁合金显微组织及沉淀析出过程的影响。结果表明,Cr元素能细化试验合金的铸态组织,并能部分打断β-Mg17Al12网状组织,且三元相τ-Mg32(Al,Zn)49、AlMg4Zn11、CeCuAl3及颗粒状Al4Cu9相在晶内呈弥散析出,并形成新相CrSb2。试验合金的时效沉淀过程中显微组织的演变过程为:过饱和固溶体→溶质原子偏聚→呈蠕虫状聚集分布的有序相→过渡相→呈(短)杆状或粒状稳定相。合金元素Cr能加速时效初期原子偏聚和晶核形成速度,增加时效后期析出相的稳定性、抑制析出相的长大。Effects of Cr on microstructure and precipitation process of Mg-10Zn-2Al-1Cu alloy were investigated by SEM(scanning electron microscope)and XRD(X-ray diffraction).It is found that Cr can refine the microstructure of the alloy by partly brokening the network structure of β-Mg17Al12 phase,resulting in the dispersed precipitation of ternary τ-Mg32(Al,Zn)49,AlMg4Zn11,CeCuAl3 phases and Al4Cu9 particle and creation of CrSb2 phase.Evolution of microstructure of the alloy during aging deposition is as follows:supersaturated solid solution→segregation of solute atoms→an vermiculate orderly distributed phase→the transition phase→(short)rod-shaped or granular stability.Cr can accelerate atomic segregation and nucleation rate at early aging and increase the stability of precipitates as well as inhibiting the growth of precipitates at latter aging.

关 键 词：CR MG-ZN-AL合金 沉淀析出 时效 

分 类 号：TG146.22[一般工业技术—材料科学与工程]