Today, we will follow Jinan Hongjie mould Co., Ltd. to understand the factors of Shandong Aluminum Alloy Die Casting peeling.
Analysis of peeling factors of aluminum alloy die casting
1 macroscopic shape of cold insulation
The macroscopical shape of the cold shut refers to the discontinuity or instability of the filling of the metal liquid due to the pressure change during the die casting. When the temperature of some molds is low, a small amount of liquid entering the mold cavity first meets the mold wall and immediately solidifies into a skin layer. The skin layer will soon be oxidized into a very thin metal layer by water vapor and oil smoke, and then the metal liquid entering the mold will mask and solidify on its surface to form the interface of the layer. Due to the oxidation of the interface between the layer and the substrate, the strength of the interface is relatively low. Under the effects of the pulling force of demoulding, the expansion force of the external gas and the external forces such as low temperature, shot peening and low pressure, the surface simply peels off.
There are micro pores under the skin
Some desquamation is the result of the release of subcutaneous gas pores under the effect of external forces. If there is no obvious peeling on the surface of the casting after indirect die-casting, but it is indicated after shot peening of the casting. The greater the strength of shot peening or the longer the time is, the more strict the peeling weather will be. This is due to the peeling disease caused by micro pores and bubbles on the surface or under the skin of the casting.
3. Poor surface precision
Some desquamation is caused by the damage of the precision layer caused by the external force because of the inaccuracy or poor meshing of the surface of some castings. After shot blasting and low-pressure cleaning, the casting shows a semi drop phenomenon because the surface layer with the thinnest adsorption force is damaged and then flanged or dropped under two pressure blows.
The above is the introduction of Shandong Aluminum Alloy Die Casting peeling factor analysis by Jinan Hongjie Die Co., Ltd! For more product information, please visit http://www.jnhjgs.cn