Research On Vacuum Investment-Suction Casting Process Of Bronze Art Works

Vacuum investment-suction casting is a precision moulding process, and is mainly applied into aviation and spaceflight,industrial turbines,medical treatment and automobile etc. But it's a new attempt to apply vacuum investment-suction casting to hollow thin-wall bronze art castings.First of all, the equipment used to manufacture hollow thin-wall bronze art castings was designed and manufactured. The equipment mainly includes suction casting device,rotating and sustaining device and circuit and gas circuit control equipment. After the equipment came into use, it showed its character of stable performance and flexible operation. Secondly, research on novel investment shell process used to vacuum investment-suction casting was carried out elaborately, and a hybrid -binder investment shell was prepared. The hybrid binder is made from ethyl silicate and silica sol binder, and possesses advantages of both binders. Compared with ethyl silicate, it is more suitable for investment precoat, the stability of the coat made from it is excellent, it does not need to desiccate by ammonia, and the procedure is simple, Both its normal temperature strength and its high temperature strength are higher than that of ethyl silicate. Compared with silica sol binder, the wettability of coat has improved greatly owe to the existence of ethyl silicate, drying time of shells cut down, and both its normal temperature strength and high temperature strength are higher than that of silica sol binder. Experiments and practical application show that the strength and air permeability of the hybrid-binder investment shell can meet demands for vacuum investment-suction casting. In conclusion, research on processing parameters of vacuum investment-suction casting was carried out. The primary processing parameters are suction vacuum level,suction temperature and freezing time. Experiments show that art castings of porcelin appearance, clear outline and figure and uniform wall thickness can be manufactured through optimized processing parameters.