Cold shut in die castings refers to defects caused by the solidification of metal liquid in certain parts or areas due to the excessive cooling rate in certain parts or areas when the metal liquid fills the mold during the filling process. This affects the sealing, strength and appearance of the part. The following are some common causes of cold shut problems in die castings and their corresponding solutions:

1. Mold design issues:

Cause of the problem: The mold structure design is unreasonable, resulting in uneven cooling speed of the metal liquid during the filling process.

Solution: Optimize the mold design, add a cooling system, adjust the mold structure to improve the fluidity of the metal liquid in the mold, ensure uniform filling of the metal liquid and avoid excessive cooling speed.

2. Improper temperature control of metal liquid:

Cause of the problem: The temperature of the metal liquid is too high or too low, which may lead to uneven cooling speed and the formation of cold insulation.

Solution: Strictly control the pouring temperature of the metal liquid to ensure pouring within a suitable temperature range to avoid excessive temperature gradients.

3. Gating system design issues:

Cause of the problem: The design of the pouring system is unreasonable. If the pouring port is improperly designed or positioned inappropriately, it may cause the metal liquid to form a cold seal during the filling process.

Solution: Optimize the design of the pouring system, adjust the position and shape of the pouring opening, increase the pouring opening or change the pouring direction to promote the flow and filling of metal.

4. Composition and solidification of metal alloys:

Cause of the problem: The composition of the metal alloy is uneven or the solidification is poor, which may cause the metal liquid to solidify unevenly during the filling process, forming a cold seal.

Solution: Optimize the formula of the metal alloy, strengthen the mixing and homogenization of the metal liquid, and ensure the solidification and fluidity of the metal liquid.

5. Improper operation:

Cause of the problem: Improper control by the operator during the die-casting process, such as excessive pressure, temperature or speed, may also cause the metal liquid to form a cold seal during the filling process.

Solution: Train operators to ensure they understand and correctly implement operating procedures, strictly control die-casting parameters, and avoid operating errors.

Through the above measures, cold shut problems in die castings can be effectively prevented and reduced, and the quality and reliability of die castings can be improved.