With the continuous expansion of the application range of aluminum alloy die-casting products such as aluminum alloy in the market, aluminum alloy die-casting parts such as domestic aluminum alloys have developed rapidly in recent years. In the current market conditions, whether it will be restricted by certain factors, this is also a concern of many people in the industry. Die-casting aluminum alloy, it is also a kind of die-casting part. The knowledge introduced below is also about die-casting parts. So what are the specific introductions?
1. Control of alloy composition Starting from the purchase of alloy ingots, the alloy ingots must be based on ultra-high purity aluminum, plus alloy ingots made of ultra-high purity aluminum, magnesium and copper. The supplier has strict composition standards. High quality aluminum alloy is the guarantee for the production of high quality castings.
2. Purchasing the alloy ingots to ensure a clean and dry stacking area to avoid white rust when exposed to moisture for a long time, or to be contaminated by factory dirt to increase the generation of slag and also increase metal loss. A clean factory environment is very effective in controlling the composition of the alloy.
3. The ratio of new material to nozzle and other materials is not more than 50%, and the new material is: old material = 70:30. Aluminum and magnesium are gradually reduced in continuous remelting alloys.
4. When the nozzle material is remelted, it is necessary to strictly control the remelting temperature not to exceed 430 °C to avoid the loss of aluminum and magnesium.
5. The conditional die-casting factory preferably uses a concentrated furnace to melt the aluminum alloy, so that the alloy ingot and the recycled material are uniformly proportioned, and the flux can be used more effectively, so that the alloy composition and temperature are kept uniform and stable. Electroplating waste and fines should be separated into separate furnaces.
Many times, it is not possible to pay attention to the above problems to make high-quality aluminum alloy die-casting parts. If the following defects occur in aluminum alloy die-casting parts, some treatments are provided below.
Since each defect is caused by a number of different influencing factors, it is necessary to solve the problem in actual production. In the face of many reasons, is it the first to adjust the machine? Or do you want to refuel? Or modify the mold first? The degree of ease, first simplified and then complicated to deal with, the order:
1) Clean the parting surface, clean the cavity, clean the ram; improve the coating, improve the spraying process; increase the clamping force and increase the amount of metal poured. These measures can be implemented by simple operations.
2) Adjust process parameters, injection force, shot speed, filling time, mold opening time, pouring temperature, mold temperature, etc.
3) Refueling, selecting high-quality aluminum alloy ingots, changing the ratio of new materials to recycled materials, and improving the melting process.
4) Modify the mold, modify the pouring system, increase the ingate, add overflow tank, exhaust slot, etc.
For example, the reasons why the die casting produces flashing are:
1) Die casting machine problem: The clamping force is not adjusted correctly.
2) Process problem: The injection speed is too high, and the pressure shock peak is too high.
3) Mold problem: deformation, debris on the parting surface, inlays and sliders are not flushed, and the template strength is not enough.