Prevent porosity in die casting includes optimize mold design, control pouring parameters, refining and degassing, and so on.
Preventing the formation of pores in aluminum alloy die castings is an important measure to improve product quality and performance.
1. Prevent porosity in die casting: optimize mold design
Mold design is a key step in reducing pores. By properly designing the exhaust system (such as setting exhaust grooves, overflow grooves and cooling channels), the gas in the mold can be effectively exhausted, thereby reducing the formation of pores.
In addition, ensure that the mold wall thickness is uniform to avoid shrinkage pores caused by uneven thickness.
2. Prevent porosity in die casting: controlling pouring parameters
Pouring speed and temperature have a direct impact on the formation of pores. Too fast a pouring speed will cause turbulence in the mold, trapping air and forming pores.
Therefore, appropriately reducing the pouring speed and controlling the pouring temperature can effectively reduce the formation of pores.
3. Prevent porosity in die casting: vacuum die casting technology
Vacuum die casting is an effective method to reduce porosity. By forming a vacuum environment in the mold cavity, the content of air and gas can reduce, resulting in a denser casting.
Studies have shown that vacuum die casting can significantly reduce porosity and size and improve the mechanical properties of castings.
4. Refining and degassing
During the aluminum alloy smelting process, the use of high-quality refining agents and degassing devices can reduce the gas content in the aluminum liquid and prevent the gas from entering the mold again. It is also necessary to remove the slag and oxides on the liquid surface in time.
5. Choosing the right release agent
Using a release agent that does not generate gas can avoid introducing additional gas during the die casting process. In addition, ensuring that the mold venting is unobstructed, especially the venting channel where the aluminum liquid finally aggregates, can further reduce the formation of pores.
6. Adjusting process parameters
Controlling pouring temperature, negative pressure and mold temperature is an important means to reduce pores. For example, increasing the pouring temperature can reduce the moisture and other volatile substances in the aluminum liquid, thereby reducing the formation of pores.
7. Material selection
Using aluminum alloy materials with good fluidity and low gas solubility can reduce the formation of pores. For example, increasing the silicon content in the aluminum liquid can reduce the porosity during vacuum die casting to a certain extent. But it should note that too high a silicon content will make the casting brittle.
8. Subsequent processing
For castings that have already produced pores, their performance can improve through subsequent processing. (such as machining or heat treatment). For example, during the machining process, try to avoid cutting the part containing pores to reduce the impact on the performance of the casting.
9. Quality control and testing
Non-destructive testing techniques (such as X-rays, ultrasound, etc.) can be used to effectively detect pores in castings.
By analyzing the test results, process parameters can be adjusted in a timely manner to optimize the production process.
Preventing the formation of pores in aluminum alloy die castings requires multiple aspects such as mold design, pouring parameters, refining and degassing, material selection, etc., combined with advanced technologies such as vacuum die casting to ensure the quality and performance of castings.
Haichen die casting machine
Haichen is one Chinese die casting machine manufacturer for more than 10years. At the same time, we produce both high pressure cold chamber die casting machine and hot chamber die casting machine. They have durable and highly precise features.
Haichen also produce die casting machine auxiliary equipment. Such as conveyor, vacuum machine, mold temperature controller, industrial robot, sprayer and so on.
We supply cold chamber and hot chamber die casting machine spare parts.
Welcome contact us.
