The difference between die-casting mold structure die casting and die casting mold forging
China has become the international castings and forgings country(including die casting, general casting, forging, etc.) production, a growing number of countries of Europe and the United States Japan and South Korea Australia, including the region of its original self-produced or newly developed products, transfer production to China with the typical cost and technology advantages. There are two rough forming process, they produce rough exterior appearance is often similar to non-professionals very good at, is generally not easy to separate the die castings and die forging (liquid forging).
Die-casting mold structure die casting and die casting forging difference between proposed to distinguish between die casting and die forging (liquid forging), at least two types of factory units meaningful:
First, some intermediate agencies, including components and parts manufacturers. They undertake external components, and then find some manufacturers in the country. These two rough its production processes vary, the current market price is not the same, which offer general than the former. If not distinguish between the two rough castings cheap quoted in carrying on the business offer, such as press, there will be mistakes in the operation of impact benefits or even losses;
The second is a professional casting and forging manufacturer. That the latter die castings can be produced using conventional die-casting process, the business took off. After die-casting mold, basically due to the Die Casting Process rough exist Shrinkage defects or the appearance of defects, rough fail to ultimately result in undue loss.
2 die forging, liquid die forging and casting and forging process the relationship between
Continuous casting and forging the nature of the process, a device with a mold, the mold filling and forging to complete a row. Continuous casting and forging process is not a new process, the principle has a long history. The most typical and most simple continuous casting and forging process, we are familiar with the liquid forging (molten forging) process. Die forging process, the image that is a higher degree of automation equipment, production structure and die castings and liquid forging. So, casting forging of common die casting in appearance difficult to separate the
Similar to the quality of continuous casting and forging process to produce the rough, the first casting, forging "process. The first casting forging process is very common: rough production totaling two sets of molds, one for the hand-ordinary metal casting, the other is used for friction punch or hydraulic press to complete the precision forging. Die forging process is the recent rise in the international process, patented technology, the technology in China is still rare.
3 die-casting forging process Profile
Die forging process is a dedicated die forging machine to complete the process. The basic process is: the liquid metal first low-speed or high-speed casting, filling into the mold cavity of the mold cavity surface activities, forging pressure with the liquid metal cooling process, both to eliminate the blank shrinkage reduction porosity, but also to the internal organization of the rough forging state broken grain. Rough overall mechanical performance has been significantly improved.
In addition, the rough outer surface finish of the production process out of reach the 7 (Ra1.6.), Such as cold extrusion process or machined surface with a metallic luster. Therefore, we will die forging process known as the "limit forming process than cutting, less margin forming process a step further. Die forging process has another advantage, in addition to the production of traditional casting material, it can wrought alloy, wrought alloy to produce the structure is very complex parts. These alloy grades including: hard aluminum, super-hard aluminum alloy, wrought aluminum alloys, such as OF LY11, LY12, 6061,6063, the LC, LD, and so on.
Tensile strength than ordinary cast alloy nearly to double to reach 400-600Mpa, aluminum alloy car wheels, frame and other parts with higher strength impact resistant material production, have a more positive meaning.
4 how to distinguish between these two rough
Shape, it is difficult to distinguish between these two processes of production out of the rough. If you see a processed parts even harder to distinguish. Therefore, we can only reversed the analysis and judgment:
First, die castings are generally structure, die forging functional parts. "Structure", and "functional parts" is relative. The latter generally refers to withstand impact, temperature, pressure, strength (force), and to surface treatment (such as anodic oxidation), heat treatment (solid solution strengthening). The typical product of the engine block, wheels, pistons, connecting rods, brake shoes, pneumatic or hydraulic valve body (such as the common 5/3-way) and so on. The former, such as door frames, instrument panels, engine cover.
Die-casting mold structure of two is to judge from the material composition. Because die castings are generally casting class alloys, for other grades of alloy die forging process of production.
Third, to judge from the rough on its outer surface processing requirements. Such as aluminum die casting, because it contains silicon camera in contact with a piece stamping die design, the back cover of plastic alarm clock injection mold design (with a full set of 3D mold). Produced by the rough and due to the die casting process, the outer surface of the micro-pores (commonly known as the "Watermark"), this material is anodized surface will be "black spots". Rough if asked anodic oxidation, the blanks are not produced with an ordinary die-casting process.
Fourth, to judge from the microstructure. Die casting and die casting forging in metallographic on our easy to distinguish. The former is a dendritic cast structure, which is a uniform grain crushing forging Structure.
5 eliminate some of the mistaken view
First, we have not to vacuum infiltration after the die-casting, to solve the Die Casting Shrinkage defects exist, can not be expected to graduate design injection mold vacuum die casting process can produce continuous casting and forging process to produce functional parts. When the line technology has been progress, ideas, and ideologically, we should have a scientific attitude of advancing with the times.
Second, vacuum die casting and common die casting, as there Shrinkage defects; vacuum die, it is only in the auxiliary exhaust than the average die-casting of a little role in the process, the metal-liquid phase transition contraction contraction hole and shrinkage (internal vacuum, no gas), it is no way.
Professionals most likely to commit errors, is that although only rough can not use ordinary die-casting process to produce, but the choice of the type known as "reverse punch indirect and partial extrusion of the production process. They think this process and the effect of liquid forging process, and this is completely wrong. Reverse punch to squeeze the essence of the process, it is still a die-casting process Forward punch kind of full projected area of the forging is the only true liquid forging process.
6 Concluding remarks
Distinguish between common die casting and die casting forging or meaningful. Although the master is not difficult, many or concepts and skills in understanding. But with the above "common sense" without pay "tuition fees", "value for money