Study On DC Casting Of Stainless Steel Clad By Pure Aluminum

This study focus on strainless steel-pure aluminum hollow tubular sputtering target by the solid-liquid composite semi-continuous casting.In this paper, according to the characteristic of steel/Al composite, a mathematical model is established to describe the process of casting of steel/Al composite ingot. The mathematical model can accurately describe the temperature field and the flow filed of the process of the casting of the composite ingot and the process of solidification of the composite ingot. Tubular ingots of steel/Al composite were made by Direct water-cooling semi-continuous, and the characteristics of the surface morphology, macroscopic and mechanical property were analyzed, finally the mechanism of Fe/Al composite formation was confirmed. The following conclusions are obtained:(1) The simulation calculation shows that with the increasing of the casting speed, the contact time between stainless steel and Al decreases. The depth of the liquid cave of Al increases with the increasing of the pouring temperature, the contact time between stainless steel and Al increases;(2) The diffusion reaction between stainless steel and Al melt is:FeAl3has the priority to form along the interface between steel and Al?the thickness of FeAl3 ayer increases ?Fe2Al5phase and FeAl2 phase emerge at the surface of FeAl3 phase near the side of steel matrix ? Al+FeAl3 eutectic structure forms in the Al matrix;(3) The thickness of the compound at the interface between steel and Al decreases with the increasing of the casting speed, so is the distance of elements in the steel matrix diffusing into Al. These two figures increase before they drop down with the increasing of the pouring temperature;(4) The fracture mechanism of samples is brittle fracture. The shearing strength rises with the increasing of the thickness of compound layer. The shearing strength is related to the type and the quantity of phases and whether the phases are well-distributed. If the compound layer is thin, there would be few species of phases as well as the interfaces between different phases in it, so the shearing strength would be high;(5) According to the shearing strength of samples, the best technological parameters have been obtained with which the production of composite ingot with high interfacial bonding strength can be guided:pouring temperature is 800 ? and casting speed is 150mm/min.