摘要
采用超声波化学镀的方法,在SnO2粉末表面包覆Ag,获得超细的Ag-SnO2复合粉末,并用粉末冶金工艺,制备出AgSnO2触头材料。研究中发现,粉末中存在的杂质导致AgSnO2材料的压力加工性能显著下降。通过金相组织及电子显微镜(SEM)的形貌观察、能谱成分分析(EDX)等手段,对烧结试样的组织进行了深入研究。结果表明:化学镀银时所用AgNO3中的杂质阻止了Ag-SnO2粉末在烧结过程的融合长大,导致粉末之间形成大量的孔洞及三角界面。使粉末之间结合力下降,材料的压力加工性能变差。基于上述研究结果,制备出密度为9.98g/cm3,电阻率低至2.13μΩ·cm,并具有优异的加工性能的AgSnO2材料。
Ultrafine AgSnO2 composite powders were prepared by ultrasonic wave enhenced electroless silver plating on SnO2 particles. The powders were then sintered by powder metallurgy to produce AgSnO2. electrical contact materials. It has been found that the press wording performance of AgSnO2 materials falls down obviously due to the impurity in coated powders. Metallurgical structure and morphology of AgSnO2 materials were investigated by optical microscope, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The results indicate that the coalescence between the Ag-SnO2 powders was inhibited by the impurity in AgNO3 used for silver plating. Voids and triangular interfaces were found in AgSnO2 materials, reducing the bond strength between Ag-SnO2 powders. By using the method of electroless silver plating on superfine SnO2 powder, the AgSnO2 material with excellent press working performance was prepared. The electrical resistivity and density of AgSno(2) are 2.13 mu Omega(.)cM and 9.98 g(.)cm(-3), respectively.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2005年第6期886-890,共5页
Rare Metal Materials and Engineering
基金
科技部"中小企业创新基金"资助(02C26213310205)
关键词
AGSNO2电触头
化学镀银
杂质
AgSnO2 contact materials
electroless silver plating
impurity