摘要
粉煤灰经热碱液活化后,采用葡萄糖作还原剂,通过向碱性溶液中缓慢滴入Ag NO3溶液的方法制备了镀银复合粉体。采用扫描电镜、能谱仪和X射线衍射进行形貌观察及成分分析,并探讨了热处理对镀银复合粉体的影响。结果表明:热处理对镀银复合粉体的导电性和晶粒尺寸影响较大。随保温温度的升高,复合粉体的电阻率先减后增,而镀层的平均晶粒尺寸则一直在增大;随保温时间的延长,电阻率和晶粒尺寸都呈先减后增的趋势。适当的热处理能够消除镀层生长缺陷,改善复合粉体的导电性。镀银复合粉体在250℃保温40 min后电阻率达到0.011Ω·cm。
Electroless silver plating on the surface of fly ash cenospheres was prepared by slowly adding the solution of AgNO3 into the mixed solution of D-glucose solution and alkaline solution after thermo-alkaline treatment. The morphology and composition of the silver-coated fly ash cenospheres composite powders were observed and analyzed by SEM, EDS and XRD, and the influences of heat treatment on silver plating were investigated. The results show that, the heat treatment has obvious influence on the conductivity of composite powder and the grain size of plating silver. With the temperature increasing, the electrical resistivity of the powders descends and then rises, while the average grain size of the plating still increase. However, both the electrical resistivity and the grain size descend and then rise with the increase of holding time. Proper heat treatment can eliminate coating growth defects and improve conductivity of the composite particles. The electrical resistivity can reach 0.011Ω. cm after heat treatment at 250 ℃ for 40 rain.
出处
《热加工工艺》
CSCD
北大核心
2014年第24期213-216,226,共5页
Hot Working Technology
关键词
粉煤灰
热碱活化
化学镀银
热处理
电阻率
fly ash cenospheres
thermo-alkaline activation
electroless silver plating
heat-treatment
electrical resistivity
