The Preparation Of Cu-Cr Alloy With Heat Mechanical Alloy

The Cu-Cr alloy unified the high degree of hardness of Cr and the good electric conduction thermal conductivity of Cu, The Cu-Cr alloy is widely used in the preparation contact material, the resistance welding electrode, the conticaster crystallizer inside lining, the integrated circuit lead frame, power tool’s diverter, the electrician switch, the anti-friction material, large-scale high speed turbine-generator rotor wire, cable car and aspects and so on.This paper is on the basis of the traditional mechanical alloying, through the experimental techniques and test installations ware improved in order to make up the conventional routes the insufficiency. In this experiment the precursors synthesized by chemical precipitation method as raw materials, in order to make the powder well-dispersed and tiny before the mechanical alloying. The alloying process carried on in a new equipment developed by Professor Shao Zhongbao, the balls and the pot of the equipment were all made by pure Cu avoided as a result of introducing the impurity, and calcination, restore response and ball milling carried on in the pot at the same time, it not only made the restore temperature effective reduced, but also avoided as a result of introducing the impurity.Different precursors were synthesized by co-precipitation method and sol-gel method. Different CuO-CrO3powders were prepared by changing different precipitators, controlling the pH value of solution, changing different drip rate, the calcination temperature, heat preservation time and so on. The CuO-CrO3powder was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and screen analysis. Experimental results show the best preparation techniques of powders:The precursors were synthesized by chemical precipitation method and choosing Cupric nitrate trihydrate and chromium nitrate nonahydrate as raw materials; NH3-H2O was used as precipitator; drip rate is4s/d; pH=7～7.5; Past a long aging times, calcination temperature for500～600℃The mechanical alloying process carried on in the vibration high temperature-energy ball milling equipment. Different Cu-Cr powders were synthesized by changing reducing agent, the ball milling temperature, the ball milling time and ball material ratio. The Cu-Cr powder was characterized by X-ray diffraction (XRD) and screen analysis. Experimental results show the best preparation techniques of powders:activated carbon was used as reducing agent; ball milling temperature is325℃; ball milling time is3h; ball material ratio is15:1.