A356 alaşımı T6 ısıl işlem optimizasyonu

In this study, the effect of heat treatment stages on the yield-ultimate tensile strength, the hardness and the elongation of the wheels produced by low-pressure die-casting technology using Sr-modified A356 alloy, is examined. The study consists of fundamentally four steps as follow; investigation of the effect of current heat treatment stages and dye process, the effect of the solution treatment on the eutectic silicon morphology and the mechanical properties, determination of the main factors affecting the mechanical properties through the design of experiment and optimizing the conditions, and the effect of the quenching phase on the cooling rate and the mechanical properties. The experiments were carried out with temperature controlled laboratory furnaces. Tensile and hardness testing was applied to the specimen taken on the wheel and microstructure analyzes were performed by using an optical microscope. As a result of the study, it was determined that 480°C is not sufficient to provide a supersaturated solution for catalyzing the precipitation hardening and the elongation values can be enhanced through the proper spherodization of the eutectic silicons. Solution treatment has no effect on yield-ultimate tensile strength and hardness by oneself. Whereas it was determined that values vary considerably when the same aging or painting process applied after different solution treatments. According to design of experiment and regression analysis, the formulas were obtained based on solution temperature, solution time, artificial aging temperature, and artificial aging time. Optimal heat treatment parameters were determined for desired mechanical properties. Cooling rates and Leidenfrost points were obtained at different quenching mediums.