高强高导Cu-Cr-Ti合金及复合材料的组织性能研究

发布时间：2018-03-28 09:01

  本文选题：Cu-Cr-Ti　切入点：原位复合材料　出处：《江西理工大学》2015年硕士论文

【摘要】：本文利用中频感应熔炼铸造及真空感应定向凝固铸造分别制备了Cu-Cr-Ti合金和Cu-Cr-Ti原位复合材料,并进行了冷拔及热处理,研究Cu-Cr-Ti合金及复合材料的组织演变规律、组织热稳定性。通过导电率测试和室温拉伸试验等检测方法,研究了挤压、固溶处理、冷拔和中间退火及时效处理等对Cu-Cr-Ti合金的抗拉强度、导电性和软化温度等性能的影响;采用X射线衍射分析技术、扫描电子显微分析方法、能谱分析技术、金相分析等分析方法,研究了Cu-Cr-Ti合金的组织特征、第二相的形貌和分布以及Cu-Cr-Ti原位复合材料的定向凝固组织特征、变形组织及热处理后的热稳定性、相成分、形貌和分布。研究结果表明:Cu-Cr-Ti合金在拉拔过程中,随着形变量的增加,纵向晶粒变成纤维状,横向组织发生不规则变形,抗拉强度增加而导电率下降,退火后抗拉强度降低导电率升高;时效处理后,Cu-0.53Cr-0.11Ti、Cu-0.33Cr-0.05Ti、Cu-0.53Cr-0.05Ti合金在400℃/2h获得较高导电率和抗拉强度,分别为73.2%IACS和640MPa,83.1%IACS和590MPa,78.6%IACS和623MPa;取合金时效峰值点在470℃~545℃间选择6个温度进行保温30min,计算得到Cu-0.53Cr-0.11Ti、Cu-0.33Cr-0.05Ti、Cu-0.53Cr-0.05Ti合金的软化温度分别在530℃、545℃、530℃左右,符合接触线材料软化温度要在500℃以上的要求。随着形变量的增加,Cu-11Cr-0.85Ti定向凝固复合材料组织发生明显变化,表现为纵向组织中Cr相由棒状逐渐转变为纤维状,横向组织中Cr相纤维宽厚比增大,呈不规则弯曲和扭曲;形变Cu-11Cr-0.85Ti定向凝固复合材料时效后材料局部细小纤维组织发生熔断及球化,并伴有球链状组织,粗大纤维组织没有发生明显的粗化现象,合金纵截面上还可以看到较为完整的纤维组织,纤维较为稳定,可见形变Cu-11Cr-0.85Ti原位复合材料具有优良的热稳定性。
[Abstract]:In this paper, Cu-Cr-Ti alloy and Cu-Cr-Ti in-situ composite were prepared by medium frequency induction melting casting and vacuum induction directional solidification casting respectively. The microstructure evolution of Cu-Cr-Ti alloy and composite was studied by cold drawing and heat treatment. The effects of extrusion, solution treatment, cold drawing, intermediate annealing and aging treatment on the tensile strength, electrical conductivity and softening temperature of Cu-Cr-Ti alloy were studied by means of conductivity test and room temperature tensile test. The microstructure of Cu-Cr-Ti alloy was studied by means of X-ray diffraction, scanning electron microscopy, energy spectrum analysis and metallographic analysis. The morphology and distribution of the second phase, the microstructure characteristics of directional solidification of Cu-Cr-Ti in-situ composites, the thermal stability, phase composition, morphology and distribution of the deformed microstructure and heat treatment were also studied. With the increase of shape variables, the longitudinal grain becomes fibrous, the transverse microstructure becomes irregular deformation, the tensile strength increases, the conductivity decreases, and the tensile strength decreases after annealing. After aging treatment, Cu-0.53Cr-0.11TiPCu-0.33Cr-0.05Ti-0.53Cr-0.05Ti alloy obtained high conductivity and tensile strength at 400 鈩，

本文编号：1675643