高压时效处理对Cu54.27Cr45.73合金力学性能及电导率的影响

在3 GPa压力作用下对Cu54.27Cr45.73合金进行不同工艺的时效处理,通过硬度、压缩屈服强度和电导率测试及显微组织观察,探讨了高压时效处理对合金力学性能及电导率的影响。结果表明:高压时效处理能改善合金的力学性能及电导率,该合金经960℃×1 h(固溶)+在3 GPa压力下480℃×1 h的时效处理后可获得较高的力学性能和电导率,其硬度、压缩屈服强度和电导率分别为181 HV、249 MPa和17.86 MS/m,与相同时效温度和时效时间的常压时效处理合金相比,合金的硬度、压缩屈服强度和电导率分别提高17.53%、5.06%和4.94%。

高压时效处理对熔渗态Cu-W合金组织及性能的影响

对熔渗态Cu-W合金分别进行不同工艺的常压和高压时效处理,利用金相显微镜、扫描电镜、透射电镜、硬度计及电阻率测试仪,对比分析了两种时效工艺所获得合金的显微组织及力学和导电性能的差异,探讨了高压时效处理对Cu-W合金组织及性能的影响。结果表明,高压时效处理能增大Cu-W合金的致密度,使组织中的析出相分布更加弥散细小,改善了Cu-W合金的力学性能及导电性能。该合金经950℃×1 h固溶后,再在3 GPa压力下500℃时效1 h处理可获得较高的硬度、压缩屈服强度及较低的电阻率,分别为164 HV、221 MPa和4.415×10-8Ω·m,较相同工艺常压时效处理后合金的硬度和压缩屈服强度分别增加了21.48%和31.55%,而电阻率却降低了8.89%。

高压时效处理后铜合金的组织与热物理性能

利用金相显微镜、扫描电镜、透射电镜、热常数测试仪和膨胀仪,测试分析了高压时效处理后铜合金的组织与热物理性能。结果表明,高压时效铜合金组织较致密且析出相弥散细小,高压时效铜合金的热扩散系数随着加热温度的升高先升高后降低,当加热温度为300℃时出现高峰值,其热膨胀系数随着加热温度的升高增大幅度较平缓,其值大于常压时效铜合金的热膨胀系数。

高压时效处理对铜基多元合金硬度的影响

对一种铜基多元合金进行高压时效处理,探讨了高压时效处理对铜基多元合金硬度的影响。结果表明:高压时效处理能提高铜基多元合金的硬度,经950℃×1 h固溶+4 GPa压力下500℃×1 h的时效处理后,铜基多元合金可获得较高的硬度值(142 HV),较处理前和常压时效处理的分别提高了40.59%和20.33%。

高压时效处理对Cu-51.15W-0.24Cr合金组织和性能的影响

针对Cu-W合金的强度和导热导电性偏低问题,对Cu48.61W51.15Cr0.24合金进行了高压时效处理,并对比了高压时效处理和常压时效处理后合金的微观组织,硬度,热导率以及导电率。结果表明:高压时效处理能增大Cu48.61W51.15Cr0.24合金的致密度,使组织中析出的Cr相更加弥散细小,改善合金的硬度及导热导电性能。该合金经960℃/1 h固溶后,再在3 GPa压力下500℃时效1 h处理可获得较高的硬度、热扩散系数及较低的电阻率,其值分别为1540 MPa、0.5236 cm^(2)·s^(-1)和4.458×10^(-8)Ω·m,较相同工艺常压时效处理后的硬度和热扩散系数分别增加了17.56%和10.74%,而电阻率却降低了4.85%。因此,高压时效处理是提高Cu-51.15W-0.24Cr合金力学性能、降低电阻率的有效途径。

Ultrahigh strength and improved electrical conductivity in an aging strengthened copper alloy processed by combination of equal channel angular pressing and thermomechanical treatment

In this paper,equal channel angular pressing and thermomechanical treatment was employed to improve the strength and electrical conductivity of an aging strengthened Cu-Ti-Cr-Mg alloy,and the microstructure and properties of the alloy were investigated in detail.The results showed that the samples deformed by the combination of cryogenic equal channel angular pressing(ECAP)and rolling had good comprehensive properties after aging at 400℃.The tensile strength of the peak-aged and over-aged samples was 1120 MPa and 940 MPa,with their corresponding electrical conductivity of 14.7%IACS and 22.1%IACS,respectively.ECAP and cryogenic rolling introduced high density dislocations,leading to the inhibition of the softening effects and refinement of the grains.After a long time aging at 400℃,the alloy exhibited ultra-high strength with obvious increasing electrical conductivity.The high strength was attributed to the synergistic effect of work hardening,grain refinement strengthening and precipitation strengthening.The precipitation of a large amount of Ti atoms from the matrix led to the high electrical conductivity of the over-aged sample.