Aluminum die casting: Aluminum alloy die casting parts porosity repair welding method

Aluminum alloy die casting A. The porosity of enrolling gas due to improper die casting parameters

In the die casting production, the die casting parameters are not selected properly, the aluminum water die casting filling speed is too fast, so that the gas in the cavity can not be completely and smoothly extruded out of the cavity, and the liquid flow of the aluminum liquid is rolled into the aluminum liquid, because the aluminum alloy surface is cooled quickly, is wrapped in the condensed aluminum alloy shell, and can not be discharged to form a larger porosity.

B. Pores caused by excessive wall thickness of the product

The shape of the product is often too large the wall thickness difference problem, often can not change the shape of the product, in the center of the wall thickness is the final condensation of aluminum water, but also the most prone to porosity parts, the porosity at the wall thickness is a mixture of separating porosity and shortening porosity, not the general method can be avoided.

C. Pores occur due to poor quality of extract degassing

In the aluminum alloy die casting production, the molten aluminum pouring temperature is generally 610ºC to 660ºC, at this temperature, there are a lot of gas dissolved in the aluminum liquid (mainly hydrogen), the solubility of hydrogen aluminum alloy is closely related to the temperature of the aluminum alloy, when the aluminum alloy condenses, there are a lot of hydrogen out in the form of bubbles exist in the aluminum die casting.

D. porosity due to poor exhaust

In aluminum alloy die casting, due to the poor exhaust channel of the mold and the poor structure of the mold exhaust planning, the gas in the mold cavity can not be completely and smoothly discharged during die casting, and there are pores in some fixed parts of the product. This kind of porosity formed by the gas in the mold cavity is large and small, and the inner wall of the porosity is the oxidation color of aluminum and air oxidation, which is different from the porosity of hydrogen separation. The inner wall of the hydrogen separation porosity is not as lubricated as the air hole, and there is no oxidation color, but the inner wall of the gray bright.

E. Porosity and shrinkage due to the shortening of aluminum alloy

The aluminum alloy, like other materials, is shortened during condensation, and the higher the pouring temperature of the aluminum alloy, the greater the shortening, and the single porosity caused by the shortening of the volume is present in the final condensation site of the alloy. It is irregular in shape, and in severe cases it is reticular.

The above is the introduction of aluminum die casting porosity repair welding, I hope to help you.