Zinc alloy die castings have the advantages of smooth surface, wear resistance and high precision, but the requirements of zinc alloy in the process of casting are also very high. In order to cast a higher quality zinc alloy, we must pay attention to various problems that will occur in the casting process and effectively solve them.

One of the most common defects of zinc alloy die casting in the production process is blistering on the surface of the casting, so what is the reason for blistering on the surface of zinc alloy die casting?

1. There is too much release agent or mold oil and water, and the design air flap of the mold is too small or too few, so that when the high-temperature zinc alloy slurry is injected into the mold, the gas generated by the film remover cannot be eliminated, resulting in foaming on the product.

2. The pressure of the die-casting machine is not adjusted sufficiently, which makes it difficult to eliminate the gas in the mold.

3. The nozzle is broken or not aligned.

4. The hammer in the furnace is broken.

Flow marks and patterns are one of the defects of zinc alloy die castings. To eliminate the defects of zinc alloy die castings, we must first analyze the causes of defects of zinc alloy die castings, and then take effective measures quickly and accurately.

Causes of flow marks and patterns:

1. First, the metal liquid entering the cavity forms an extremely thin and incomplete metal layer, which is made up by the later metal and leaves traces;

2. Low model temperature, such as zinc alloy mold temperature less than 150 and zinc alloy mold temperature less than 180, will produce such defects;

3. High filling speed;

4. Excessive amount of paint;

5. High cavity backpressure;

Now that we know the causes of zinc alloy die castings, let's talk about the solutions to the flow marks and patterns of zinc alloy die castings:

1. Adjust the sectional area or position of the inner gate;

2. Adjust the filling speed appropriately to change the flow state of the metal filling cavity;

3. Increase the model temperature;

4. Properly select and improve coatings;

Cold shut means that two or more strands of molten metal are not fully fused during convection. So what is the reason for the cold shut of zinc alloy die castings? How to solve it?

Cause:

1. The two metal streams are connected with each other, but they are not fully fused and there are no impurities between them, and the binding force of the two metals is very weak;

2. Low pouring temperature or model temperature;

3. Incorrect alloy composition and poor fluidity;

4. The gate is incorrect and the flow path is too long;

5. Low filling speed;

6. Low pressure;

resolvent:

1. Appropriately increase the pouring temperature and model temperature;

2. Increase the injection pressure;

3. Appropriately increase the thickness of the inner gate while increasing the injection speed;

4. Improve exhaust conditions;

5. Correctly configure alloy components to improve liquidity;

6. Avoid overheating;

Source: Changjiang nonferrous metals network