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                                                               Five methods for preventing cracks in precision casting










1. Gray iron thin-walled parts have stronger chilling effect or faster solidification speed, so the chemical composition can be reduced by one grade (or the carbon equivalent of the ingredients can be increased).
2. The crack is generated due to the stress generated during the solidification of the casting. Therefore, the casting is preferably subjected to artificial aging treatment to eliminate the stress before processing.
3. The cracks in the castings are cold cracked (the crack is relatively flat, not oxidized, the structure is very clear) and the hot crack (the crack is more tortuous, the fracture is oxidized), so it depends on whether the phosphorus and sulfur in the chemical composition exceed the standard. . Phosphorus is prone to cold cracking, and sulfur is prone to hot cracking.
4. Increase the fillet of the intersection of the castings.
5. The casting increases the lacing, and the last process removes the lacing.

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