Pt-Co-Mn合金组织结构及性能研究

Study on the Microstructure and Properties of Pt-Co-Mn Alloy

采用真空电弧熔炼制备了四种Pt-Co-Mn新型合金。借助X射线衍射仪、金相显微镜、显微硬度仪、磁性测量仪、分光光度计、电化学工作站等,研究了Pt-Co-Mn合金的显微组织结构、力学性能、磁性、反射率和耐腐蚀性。结果表明,Pt-Co-Mn合金为单相固溶体,平均晶粒尺寸为200~300μm。Co-Mn元素对Pt的固溶强化效果强于Co,Pt-Co-Mn合金维氏硬度为162HV~179HV,均高于Pt-5Co合金。向Pt-Co合金添加Mn元素后,Pt-Co-Mn合金在常温下磁性消除。其中Pt-2.0Co-2.0Mn合金平均磁化率为1.45×10^(-5),且磁滞回线增长缓慢,消磁效果最好。Pt-Co-Mn合金在可见光谱段的平均反射率为54.5%~57.8%,说明Co、Mn元素配比对合金反射率的影响较小。所分析的合金在人工汗液中表现出良好的耐腐蚀性。此外,Pt-2.6Co-1.4Mn合金具有较高的自腐蚀电位-0.032 V和较低的自腐蚀电流密度2.01μA/cm^(2)。所测得的腐蚀电位和腐蚀电流密度表明Pt-2.6 Co-1.4Mn合金具有最佳的耐腐蚀性。

Four kinds of Pt-Co-Mn alloys were prepared by vacuum arc smelting.The microstructure,mechanical properties,magnetism,reflectivity and corrosion resistance of Pt-Co-Mn alloys were studied by X-ray diffractometer(XRD),metallographic microscope,microhardness tester,magnetism measuring instrument,spectrophotometer and electrochemical workstation.The results showed that the Pt-Co-Mn alloys were single phase solid solution with an average grain size of 200—300μm.Co and Mn in solid solution were found to give a considerably higher strengthening effect than Co.The Vickers hardness of Pt-Co-Mn alloys varied from 162HV to 179HV,which was higher than that of Pt-5Co alloy.The magnetism of Pt-Co-Mn alloys could be eliminated by adding Mn to Pt-Co alloy at room temperature.In addition,Pt-2.0Co-2.0Mn alloy exhibited the lowest average susceptibility value of 1.45×10^(-5)and the smoothest hysteresis loop,which showed the best degaussing effect.The average reflectance of Pt-Co-Mn alloy in the visible spectrum ranged from 54.5%to 57.8%,which indicated that the proportion of Co and Mn elements had little influence on the reflectance of the alloy.The proportion of Co and Mn had little influence on the reflectance of the alloy.The analyzed alloys exhibited a good corrosion resistance in artificial sweat.Furthermore,Pt-2.6Co-1.4Mn alloy had higher corrosion potential value of-0.032 V and lower corrosion current density value of 2.01μA/cm^(2).The obtained corrosion potential and corrosion current density led to the best corrosion resistance of Pt-2.6Co-1.4Mn alloy.