Parallelism error accumulation, re-grinding assembly.
The holes on the push block are not vertical, so the small punch is offset and the push block is repaired or replaced.
Installation of punch or guide post is not vertical, reassembly ensures vertical.
One. Die wear
In the process of die casting, the die is always in the state of high temperature, high pressure and high impact, which inevitably causes wear and tear. In order to reduce wear, it is necessary to cooperate with demoulding agent to ensure good lubricity of the die.
Die-casting process products have a wide range of applications in our life. Now let's talk about the remarkable characteristics of aluminium alloy die-casting.
First of all, aluminum die casting has obvious advantages in the use process, because the casting has high accuracy in the process of processing, the casting surface is smooth, and will not produce rough surface. In addition, the strength and hardness of aluminium die castings are obviously better than those of common sand castings, which can be increased by 25% - 30%. In addition, aluminium die casting has good dimensional stability and can produce more complex parts types. However, in order to make casting products durable, we need to pay special attention to temperature, mold and other issues, because too high or too low temperature will have a fatal impact on parts. In addition, the production efficiency of this die casting method is very high, and the small production mode is an economic waste.
Second, corrosion failure
Commonly used dies and zinc alloys, casting alloys, aluminium alloys, magnesium alloys and copper alloys, and pure aluminium alloy die casting, zinc metal elements, aluminium, magnesium are active, they have good affinity, die materials, especially aluminium plate. When the die has high hardness and good corrosion resistance, if there are soft spots on the forming surface, it has anti-corrosion effect.
Three. Damage and Failure of Thermal Fatigue Cracks
In the production of die casting dies, quenching effect of hot forming surface and internal deformation occur from time to time, resulting in repeated cyclic thermal stress, structural damage and elastic loss, resulting in the appearance of micro-cracks, and continue to expand. When the crack propagates, the fluid diapir and metal melt, as well as repeated mechanical stress, accelerate the crack propagation. Therefore, on the one hand, the die casting die must be fully preheated to start. In addition, in the production process of die casting die, in order to prevent early cracking failure, it is necessary to maintain a certain working temperature range. At the same time, it is not a problem to ensure the production and internal reasons of the die before putting into production. Because in actual production, die failure is the biggest thermal fatigue crack failure.
1. Material impurities exceed the standard, especially lead.
2. Surface of the product is certainly not fully qualified, there should be slight water marks and bubbles. The workpiece can be heated to 150 degrees for 30 minutes to see if there is any problem. If the coating is foamed, it may be that the surface is not completely degreased and dewaxed, or that the surface is not clean after pretreatment, that the zinc alloy die castings are not completely dry before plating, or that the zinc alloy die castings are oxidized on the surface for too long.