Cr-Y共掺杂AgSnO_(2)触头材料性能的仿真与实验

Simulation and experiment on properties of Cr-Y co-doped AgSnO_(2) contact materials

采用掺杂改性的方式改善AgSnO_(2)复合触头材料的电性能和加工性能。基于密度泛函理论的第一性原理,对掺杂Cr-Y、Cr-Ce的SnO_(2)超晶胞进行弹性常数的仿真计算,筛选出力学性能较好的稀土元素Y进行电性能的仿真与实验。从能带结构和态密度分析Cr、Y单掺杂和共掺杂对SnO_(2)电子结构的影响,结果表明,掺杂后SnO_(2)能带隙减小,电子跃迁所需能量降低。采用溶胶凝胶法制备掺杂的SnO_(2)粉末,并应用XRD对其进行物相结构分析,验证了掺杂离子进入SnO_(2)晶格,形成固溶体,能实现仿真建立的替代掺杂模型。采用粉末冶金法制备掺杂的AgSnO_(2)复合触头材料,测量其密度、硬度和电导率,掺杂后AgSnO_(2)触头材料电导率提高,其中Cr、Y共掺时物理性能最优,验证了仿真结果。使用JF04D型电接触触头材料测试系统对触头材料进行电接触性能试验,试验结果表明,掺杂Cr、Y可有效降低AgSnO_(2)触头材料的燃弧能量,改善抗电弧侵蚀性,抑制电弧对触头的烧蚀,稳定触头材料的抗电弧侵蚀性能、抗熔焊性能。

The electrical and processing properties of AgSnO_(2) composite contact materials were improved by doping.Based on the first principles of density functional theory,the elastic constants of SnO_(2) supercells doped with CrY and Cr-Ce were calculated by simulation,and the rare earth element Y with better mechanical properties was selected for simulation and experiment of electrical properties.The effects of Cr and Y doping on the electrical properties of SnO_(2) were analyzed from the energy band structure and density of states.The results show that the band gap of SnO_(2) decreases and the energy required for electron transition cuts down after doping.The doped SnO2 powder was prepared by sol-gel method,and its phase structure was analyzed by XRD.It is verified that doping ions enter into the SnO_(2) lattice to form solid solution,and achieves the alternative doping model established by simulation.The doped AgSnO_(2) composite contact materials were prepared by powder metallurgy method,and their densities,hardnesses and conductivities were measured.The conductivities of doped AgSnO_(2) contact materials are improved,and Cr-Y co-doped is the best among them,which verifies the simulation results.JF04D type electrical contact material test system was used to test the electrical contact performance of contact materials.The test results show that doping Cr and Y can effectively reduce the arc energy of AgSnO_(2) contact materials,improve the arc erosion resistance,inhibit the arc ablation of contact materials,and stabilize the arc erosion resistance and welding resistance of contact materials.