In centrifugal centrifugal casting production, casting […]
In centrifugal centrifugal casting production, casting speed, casting system, casting quantity, solidification under slag, metal filtration, coating use, casting temperature, casting demolition, etc. are process problems that must be determined or solved because they directly affect castings. Quality and productivity.
The mold rotation speed is an important process factor in centrifugal casting. Different castings, different casting processes, and casting speeds during casting molding are also different.
Too low mold speed will cause poor filling of molten metal during vertical centrifugal casting, and metal liquid rain will occur during horizontal centrifugal casting, which will also cause loose and slag inclusions in the casting, and unequal unevenness on the inner surface of the casting;
The rotation speed of the mold is too high, and cracks, segregation and other defects are prone to occur on the casting. The outer surface of the sand-type centrifugal casting will form defects such as expansion boxes, and the machine will have large vibration, increased wear and excessive power consumption.
Therefore, the selection principle of the mold rotation speed should be based on the premise of ensuring the quality of the casting, and select the minimum value.
The die-casting forging process is a process performed on a dedicated die-casting die forging machine. The basic process is: the metal liquid is first filled into the cavity of the mold by low speed or high speed casting, and the mold has a movable cavity surface, which is pressed and forged with the cooling process of the molten metal, thereby eliminating the shrinkage of the blank. Loose defects also cause the internal structure of the blank to reach the forged broken grain. The overall mechanical properties of the blank are significantly improved. In addition, the blank produced by the process has an outer surface finish of 7 (Ra1.6), such as a cold extrusion process or a machined surface, with a metallic luster. Therefore, we call the die-casting forging process the “extreme forming process”, which is a step further than “no cutting, less residual forming process”.
Another advantage of the die-casting forging process is that, in addition to producing traditional casting materials, it can also produce deformed alloys and forged alloys to produce highly complex parts. These alloy grades include: hard aluminum super-hard aluminum alloy, wrought aluminum alloy, such as LY11, LY12, 6061, 6063, LYC, LD, etc.). The tensile strength of these materials is nearly twice as high as that of ordinary cast alloys. It is more positive for aluminum alloy automobile wheels, frames and other parts that are expected to be produced with higher strength and impact resistant materials.