Investigation On Mo/Cu Composite Prepared By Mechanical Alloying And Forming Process

The paper introduced the principle of mechanical alloying and commonly used means, discussed the principle of ball milling techniques, the international development of profiles, discussed the effects of process parameters on mechanical alloying. The main purpose of this dissertation concentrates to study the process of ball milling and the cold isostatic pressing(CIP) and sintering in hydrogen atmosphere. The major research contents and achievements include:Through the designing and optimizing of the MA technology,pressing of powder technology and liquid phase sinter technology, the new heavy alloy Mo-Cu was made.And the influence of those processes to the property of the Mo-Cu alloy was concluded.In the view of the process that influences the effect of ball milling and the particle size of the powder,solid solubility of alloys being guideline, the 4-factor and 3-horizontal orthodoxy experiment is designed and processed. The best process parameter combination and the influence rule for mechanical alloying is got by the application of square error analysis method. The experiment indicates that the ball-milling time, the filling coefficients, ball-to-powder weight ratio, rotate speed of ball milling machine influence the particle size and solid solubility of alloys greatly.The influences of forming pressure on sintering in hydrogen atmosphere properties of Mo-Cu composite are studied for improving further the density and properties. Through measuring the density of the sample and the copper content, the density and the copper content in different temperature was got. Results show that the sintering density is elevated and the leakage of copper is reduced with increase of forming pressure.At last,the densified mechanism was studied. There are three main stages in the high temperature sintering that bonding, the sintering neck growing and the amount and volume of the pores decreasing notably, which have the relevant sintering mechanism. The densification mathematical model founded on it and the experiment results are consistent, can explain the influence regularity of the technology factors.