铸态下Cu-Cr-Zr-Mg合金相转变及浇注温度对其性能的影响  

Phase Transformation in Cu-Cr-Zr-Mg Alloy As Casting and Effects of Pouring Temperature on Its Mechanical Properties

作　　者：陶富勇[1] 侯彬[1] 房栋[1] 王自东[1] 陆亮亮[1] 刘松[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《稀有金属》2012年第6期858-863,共6页Chinese Journal of Rare Metals

基　　金：材料先进制备技术教育部重点实验室开放课题基金(KLAMP-1102)

摘　　要：探讨了Cu-0.4%Cr-0.2%Zr-0.15%Mg合金在铸态下各相的存在形式以及浇注温度对合金力学性能的影响。Cu-Cr-Zr-Mg合金的铸造采用真空离心半连续铸造技术。离心的转速设置在150 r.min-1,离心时间为10 min。浇注温度分别设置在1120,1150,1200℃。铸造出来的试样采用SEM和EDXS分析了组织形态,发现合金组织在高倍下呈现α-固溶体单相组织,Cr,Zr,Mg和Cu形成共晶组织,这些共晶组织呈条状、点状、带状的形式均匀分布在基体中。Cr相的存在形式有两种:一种是以单质点状的形式存在于基体中,另外一种是以CrCu2(ZrMg)金属间化合物呈现环状包隔着Cu2(Zr7Mg)的形式存在于基体中。Zr相和Mg相的存在形式也有两种:一种是与Cu,Cr形成金属间化合物CrCu2(ZrMg),另外一种是与Cu形成的金属间化合物Cu2(Zr7Mg)。在力学性能方面3种浇注温度得出合金铸态下抗拉强度依次为195,212,177 MPa,合金的延伸率依次为24.2%,23.5%,22.9%。这一测试结果表明:3种浇注温度合金的延伸率比较接近,而浇注温度为1150℃时合金的抗拉强度最好,分别比浇注温度为1120和1200℃的合金抗拉强度提高9%和20%。最佳浇注温度定在1150℃。Existence forms of each phase in the Cu-0.4% Cr-0.2% Zr-0.15% Mg alloy as-cast and effects of pouring temperature on mechanical properties of Cu-0.4% Cr-0.2% Zr-0.15% Mg alloy were discussed. Cu-Cr-Zr-Mg alloy was produced by vacuum centrifugal semicontinuous casting. Centrifugal rotational speed was set at 150 r·min^-1 , and centrifugal time was set at 10 rain. Pouring temperatures were set in 1120, 1150, 1200℃. Structure of Cu-0.4% Cr-0.2% Zr-0.15% Mg alloy as-casting was analyzed by using scanning electron microscope （SEM） and energy dispersive X-ray spectrometer （EDXS）. α- interstitial single-phase organization was observed. Many elements （containing Cr, Zr, Mg and Cu） of the eutectic phase were also observed. These eutectic phases like a point or banding were distributed homogeneously in matrix. The existence of the Cr-phase form had two kinds. One was simple substance Cr like a point distributed in matrix, the other was CrCu2 （ZrMg） intermetallic compound like annular distributed in matrix, and the CrCu2 （ZrMg） around Cu2 （Zr7Mg）. The existence of the Zr-phase and Mg-phase form also had two kinds. One was CrCu2 （ZrMg） intermetallic compound, the other was Cu2 （Zr7Mg） intermetallic compound. In mechanical property aspect, tensile strengths of the alloy under different pouting temperatures respectively were 195, 212 and 177 MPa, and elongations of the alloys under different pouting temperature respectively were 24.2%, 23.5%, 22.9%. The test results showed that the elongations of the alloys were nearly the same, but the tensile strengths of the alloys were very different. The best was 212 MPa, which increased 9% and 20% compared with 195 and 177 MPa. As a result ,the best pouting temperature was set in 1150℃.

关 键 词：Cu-0 4%Cr-0 2%Zr-0 15%Mg 真空离心铸造 浇注温度 金属间化合物 力学性能 

分 类 号：TG146.11[一般工业技术—材料科学与工程]