Processing steps and cleaning methods of aluminum castings
Processing steps of cast aluminum parts:
(1) What is aging treatment? The method of heating the casting after solid solution treatment to the set temperature, leaving the furnace for a period of time, and slowly cooling it in the air is called aging. If the aging strengthening is completed at room temperature, it is called natural aging. If the aging strengthening is completed in an environment higher than room temperature and kept warm for a period of time, it is called artificial aging. Aging treatment is a spontaneous process of supersaturated solid solution decomposition, which can restore the lattice of the alloy matrix to a relatively stable state.
(2) What is annealing treatment? The process of heating aluminum alloy castings to about 300°C, holding for a period of time, and cooling to room temperature with the furnace is called annealing. During annealing, the solid solution will decompose and the second phase particles will gather, which can remove the internal stress of the casting, keep the size of the casting stable, avoid deformation, and enhance the plasticity of the casting.
(3) What is solid solution treatment? Heat the casting to almost the melting point of the eutectic, then keep it at this temperature for a little longer, and then cool it quickly, so that the strengthening components can be best dissolved, and keep this high temperature state until At room temperature, this process is called solution treatment. Solution treatment can enhance the strength and plasticity of castings and improve the corrosion resistance of alloys. The effect of solution treatment is usually related to three aspects: solution treatment temperature, solution treatment holding time, and cooling rate.
Because cast aluminum products are formed in different ways, different cleaning methods are required. Use rotating equipment to drive the flexible shaft deep into the casting tube hole for yarn clearing treatment. It is suitable for the situation where important castings cannot be vibrated and heated. The following methods are generally available:
1. Regarding sandblasting of cast aluminum parts;
2. Regarding the treatment of mechanical sand cleaning;
3. Regarding the cleaning of compressed air;
4. The cast aluminum parts are treated by sandblasting with a liquid sandblasting machine;
5. For cast aluminum parts, use a pick to vibrate the sand, heat and slightly vibrate to produce the core with cast aluminum collapsible resin, and use buried copper pipes instead of sand cores. When cleaning the casting pipeline, it can be soaked in 40-50% nitric acid. remove.