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Solutions to prevent shrinkage in the production of cast aluminum parts

To avoid the casting has shrinkage holes and shrinkage porosity, for the shrinkage and condensation characteristics of the alloy to develop a reasonable casting technology, so that the casting in the condensation link to create excellent feeding standards, as far as possible to avoid the shrinkage into shrinkage holes, and shrinkage holes occur at the end of the casting condensation area. In this way, a gate of a certain size is placed in the area of condensation at the end of the casting, so that the shrinkage hole is concentrated in one place, or the gate is opened in the area of condensation at the end of the immediate shrinkage. In order to create an excellent feeding standard for castings in the setting stage, the key factor is to control the setting direction of the casting to make it conform to the "directional setting criteria" or "co-setting criteria". The entry point of the pouring system has a key hazard to the temperature spread of the casting. Adjusting the pouring temperature and pouring rate of the liquid metal can strengthen the directed condensation or the condensation together. Setting gate on thick wall or hot joint of casting, casting aluminum is an effective process countermeasure to avoid shrinkage and shrinkage. The flexible use of gate, subsidy and cold iron is a reasonable countermeasure to remove shrinkage and porosity in castings The pressure processing deformation and die casting are effectively and closely combined together to make the aluminum workpiece get effective strength and patience cooperation method called deformation die casting; The die casting carried out in the negative pressure atmosphere or vacuum is called vacuum die casting, which can not only make the workpiece non-corrosive, non-carburizing, the surface of the workpiece after continuous treatment, and the function of the workpiece, but also carry out chemical die casting through the infiltration agent. In order to only warm the surface of the workpiece without excessive heat transfer into the workpiece, the applied heat source must have a high energy density, that is, provide a lot of heat energy on the workpiece per unit area, so that the surface of the workpiece or some can reach a high temperature for a short time or instantaneously.