Simulation On The Spark Plasma Sintering Copper And Titanium Alloy TB6 Powder And The Effects Of Mould

Spark plasma sintering (SPS) is a new sinter technology of powder that developsrapidly in recent years and it has received broad attention for its short sintering time, widerange of application. With the development of computer technology and finite elementsoftware, numerical simulation has been applied extensively in the research of SPS field.A directly coupled electric-heat transit model was built, which was code into ANSYS12.1, to simulate transient current density and temperature distribution during SPSelectrolytic copper powder under the consideration of thermal and electric contactresistance, thermal radiation, the water convection cooling and discrete sample size. Theanalysis results show that the current and temperature distribution in the sintering systemare not uniformed both in the axial and the radial directions. The current density at theedge of the sample is higher than that of the center, the temperature at the center of thesample is greater than that of the edge. The simulation results show an excellentagreement with the experimental results, and the method of discrete sample size is correct.The effects of the die sizes on the process were also analyzed. The analysis resultsshow that with deceasing radial dimension of die, current density increases; the currentdensity gradient decreases both in the die and in the sample; and the heating rate of thesintering process is increased. While with deceasing axial dimension of die, the currentdensity in the sample and the punch head is close to that of the sample; the current densitygradient and the temperature gradient in the die and the punch head all increase; theheating rate in the system is increased. As a result, the uniformity of the currentdistribution and temperature distribution, and furthermore the characteristics of sinteringmaterial can be effectively controlled by design of the die size with the benefit of greatlyshortening sintering time.The process of SPS titanium alloy TB6 is simulated, this thesis attempts to analyzethe distribution characteristics of current density and temperature within SPS system,providing optimized SPS parameters for TB6. The result shows there are obvioustemperature grads at radial direction of the sample; the highest temperature at the samplecenter reaches 1261K, and the temperature along the radical direction decreases successively.