Analyze the preheating requirements of die-cast aluminum parts
Die-casting aluminum parts need to be preheated before use. Cast aluminum molds should be preheated to a certain temperature before use. Preheating can prolong the service life of the mold. It is preheated with multi-purpose electrical appliances or induction heating. The preheating temperature is controlled at 250℃～300℃. It can be used for about 0.5h. It is forbidden to use molten metal (aluminum water) to directly preheat the mold, because the cold mold is directly in contact with the hot liquid metal, which is bound to be subjected to thermal shock, which will cause thermal erosion and accelerate the cracking caused by thermal fatigue. And peeling.
In the production process of die-casting aluminum parts, it can effectively improve the surface processing quality of the mold cavity. The surface of the mold cavity should not have obvious deep processing knife marks to prevent the mold from cracking due to stress concentration during mold work. At this time, the surface of the cavity should be effectively polished and ground to keep the surface roughness of the cavity under 0.8μm.
The cooling of die-cast aluminum parts in use. In continuous production, the temperature of the aluminum casting mold tends to increase. Excessive temperature not only causes the liquid metal to produce boulders, but also slows down the cooling of the castings, resulting in coarse grains and the quality of the aluminum castings. Therefore, when the temperature of the cast aluminum mold is too high, cooling measures should be taken. Usually compressed air or water is used to cool the cast aluminum mold. A cooling system is designed to ensure the thermal balance of the mold. It is strictly forbidden to chill the mold with cold water to avoid rapid cooling of the mold. Shrinkage will cause cracks, which will cause premature failure of the mold and shorten the service life. Of course, proper spraying of paint during the use of the mold can not only prevent the mold from sticking but also play a certain cooling effect, which is beneficial to improve the life of the mold.
The maintenance and management of die-cast aluminum parts after use. After the aluminum mold is used, the mold cavity should be cleaned in time to a certain extent to effectively remove residual aluminum. After cooling, it should be rust-proofed and stored in the warehouse. Release, centralized management, for reuse. Cast aluminum mold is an important tool in motor manufacturing, and it occupies a large proportion of motor manufacturing cost. Practice has proved that the use of new mold materials, reasonable forging, and correct heat treatment are the key links to improve the service life of aluminum casting molds; at the same time, the service life of aluminum casting molds can be effective by grasping all relevant links such as mold design, manufacturing, use, and maintenance management. Extending, the manufacturing cost of the motor is correspondingly reduced.
When the die-casting aluminum parts are manufactured in the fan slot EDM perforated electrode, the sharp edges around the electrode will be rounded to d1.5mm~2mm to ensure that there is no sharp corner transition in the mold cavity after electrical machining, and to avoid cracking and failure at the sharp corners of the mold. The correct and standardized use of cast aluminum molds, supplemented by meticulous maintenance and management, will prolong its service life.