Will the forging have an uneven texture, and will the forging knock down the impurities?

Forging does not change the metallographic structure of the metal material itself, that is, it does not change the chemical composition distribution of the material due to forging. If the depth of the same impact is different, it is because you don't control the edges and corners well. Different materials need to pay attention to different greenhouse controls.

Forging knocks down impurities.

Forging is a kind of use of forging machinery to apply pressure to the metal blank to produce plastic deformation to obtain certain mechanical properties.

The processing method of forgings of a certain shape and size, one of the two major components of forging (forging and stamping).

Through forging, defects such as loose casting caused by metal in the smelting process can be eliminated, and the microstructure can be optimized.

At the same time, due to the preservation of the complete metal streamline, the mechanical properties of forgings are generally better than castings of the same material.

Deformation temperature

The initial recrystallization temperature of steel is about 727, but 800 is generally used as the dividing line, and higher than 800 is hot forging; Between 300 and 800 is called warm forging or semi-hot forging, and forging at room temperature is called cold forging.

Forgings used in most industries are hot forging, warm forging and cold forging are mainly used for forging parts such as automobiles and general machinery, and warm forging and cold forging can effectively save materials.

The ratio of medium permeability forging reflects the relationship between the degree of deformation of the forging and the mechanical properties of the forging. The forging ratio is high, the internal structure of the material is fine, the composition is homogeneous, and the mechanical bending can be improved. However, when the forging ratio reaches a certain value, the mechanical properties of the material are not significantly improved when the forging ratio is increased.

First of all, the manufacturing process of cast and forged wheels is different. Casting is the process of melting metal into a liquid that meets certain requirements and then pouring it into a casting tool. After cooling, solidification, and cleaning, the casting essentially has a predetermined shape, size, and performance.

On the other hand, forging is a method of producing and processing forgings with certain mechanical properties, a certain shape and size, by applying pressure to the metal rafters through a forging press, resulting in plastic deformation.

The cost of both hubs is not necessarily the same. Compared to the simple and crude casting process, it is easy to produce in large quantities. Of course, the cost is lower, and the forging process is more complex, so the manufacturing cost is higher.

In addition, forged wheels are made by continuous tempering. Of course, its molecules are very dense and neatly arranged, resulting in its strength and toughness being stronger than the cast round resistance, that is, the forged hub.

In terms of weight, the raw material of forged wheels is stamped continuously during the production process, so it can withstand the pressure of higher cavity bridge height after forming. At the same time, in the case of similar size and strength, the quality of forged wheels is slightly lighter than that of cast wheels, and most of the cast wheels of Changshen are about 20% heavier than forged wheels. However, forged wheels have a disadvantage, that is, the metal ductility is not very good, and it is also relatively expensive, and most of them are suitable for high-end cars.

To sum up, I personally advocate that qualified car owners can choose forged wheels, which are safer in detail and can get a better driving experience. But if the owner thinks that forged wheels are too expensive, they can choose to use wheels made by forged embryo spinning. This type of wheel is similar to forged wheels in terms of performance, but is cheaper and more cost-effective.

In addition, when choosing a hub, riders should not only look at the type of manufacturing of the hub, but also pay attention to the structural dimensions of the hub. While oversized wheels can improve the stability of a car, they can be very poor in terms of shock absorption and comfort. Naturally, follow the advice of professionals and choose the right three-distance wheel.

Practical significance of forging ratio:

In the forging process, with the increase of the forging ratio, the internal pores are pressed, the cast dendrites are broken, and the longitudinal and transverse mechanical properties of the forgings are significantly improved. However, when the elongated forging cross-section ratio is greater than 3-4, with the increase of the forging cross-section ratio, an obvious fiber structure is formed, which makes the plasticity index of transverse mechanical properties decrease sharply, resulting in the anisotropy of forgings. If the forging cross-section ratio is too small, the forging can not meet the performance requirements, and if it is too large, the forging workload will be increased, and anisotropy will be caused.

Extension of knowledge points:

The forging ratio is a way to express the degree of deformation of the metal during forging, and is usually expressed as the ratio of the cross-sectional area of the metal before and after the deformation.

The forging ratio is usually measured by the degree of deformation when drawn. It refers to the ratio of the length to diameter of the material you want to form, or the ratio of the cross-sectional area of the raw material (or prefabricated blank) before forging to the cross-sectional area of the finished product after forging. The size of the forging ratio affects the mechanical properties of the metal and the quality of the forging, and increasing the forging ratio is conducive to improving the structure and properties of the metal, but the forging ratio is too large and not beneficial.

The forging ratio is actually the upsetting ratio of the material.

The forging ratio is an indication of the degree of deformation of the metal at the time of forging. The larger the forging ratio, the higher the degree of deformation of the forging, and the degree of deformation is directly related to the size of the final inclusion of the material, the degree of crushing of the eutectic carbide of the material, the fiber flow direction and density of the material after the final forming, etc., which has a greater impact on the comprehensive properties of the material.

At present, there are three types of process schemes to improve the uniformity of forging ratio, which are to change the boundary conditions between the blank and the die, change the shape of the blank, and change the upsetting and rough deformation mode. And by changing the deformation mode of flat anvil upsetting, the forging ratio and geometric size uniformity of forgings can be effectively improved.

The distribution of forging ratio (i.e., deformation degree) in different forging ratio forgings is uneven, and it is obviously divided into large forging ratio area, average forging ratio area and small forging ratio area. The mechanical properties test shows that under the same heat treatment conditions, the plastic deformation of a certain forging ratio can significantly improve the strength index and plasticity index of the rolled steel, when the forging ratio reaches a certain value, the microstructure of the forging changes drastically, and its strength is increased to the best, but the toughness is significantly reduced.

Under the same strain rate, the larger the forging ratio (i.e., the degree of plastic deformation), the more obvious the dynamic recrystallization in the forging structure, and when the forging ratio reaches a certain value, the original grain will be replaced by the new recrystallized grain, and a more complete dynamic recrystallization will occur. Therefore, the forging ratio has a great impact on the quality of forgings. I am an employee of Yongxinsheng, I hope you can be satisfied with me.