Preparation of ultrafine copper powder with hydrazine hydrate as reducing agent;

Because of special physical and chemical properties, ultrafine copper powders have been used in many kinds of fields, such as conduction materials, catalysts, lubricant addition, nanocrystalline copper materials, medicine and so on.

The activation pretreatment of copper concentrate has been done by high energy ball mill,and ultrafine copper powder with average size less than 10 μm has been prepared by directly using copper concentrate and ultrasonic slurry electrolysis.

The methods of thermal spray and mechanical ball milling were combined in this paper and a new method of preparation of ultrafine Cu-Zn powder was brought forward.

In this thesis,the classification of superfine copper powders obtained from chemical reduction method has been researched using a special U pipe which was designed and made by ourselves,and the particle sizes and distribution have been characterized by transmission electron microscope (TEM) and laser particle analysis instrument.

The optimum temperature, amount of ammonia, and blue copperas concentration for preparation of micro flake copper powder are determined by orthogonal test.

Study on the Optimization of Manufacturing Process and the Structure for Superfine Cu-Zn Powder Made by the Methods of Thermal Atomization and Wet Grind;

The changes of morphology and structure of fine copper powder during oxidization process were observed by SEM and TEM,and their weight gain processes were measured by thermal gravity analyser (TGA).