In recent years, the car industry has continued to rise, following the continuous expansion of the mall, people's requests to resist the function and quality of cars are also getting higher and higher. However, in the manufacturing process of the car, due to various reasons, the development cycle of the car has been lengthened, and the manufacturing difficulty is also great, which also has a certain impact on the overall progress and degree of the car, in which the car stamping parts The manufacture is a serious factor affecting the manufacture of cars, so the car manufacturers are gradually paying attention to the research and manufacture of car stamping parts. In the manufacturing process of car stamping parts, the key points must be closely combined, and it is useful to avoid all kinds of achievements that can occur in the process of childbirth. The results of the process of childbirth include the rebound results, so how to handle them properly? The rebound results are also an aspect of the overall accuracy of the promotion of the car. The following will briefly explain the types of rebound results of the automobile stampings, the reasons for the rebound results and the factors affecting the rebound.

First, the model of rebound defects in automotive sheet metal stamping parts

The first is to misinterpret the defects, including the shape misinterpretation, the shallow drawing of the piece, the multi-curve shape misinterpretation, etc., due to the punching force in the processing process, it will cause the processing process to have the shape misinterpretation of the stamping parts, in the process of punching, The punching gap is unreasonable, so that one side of the material is subjected to tightening, and the other side is subjected to the pulling, so that the stamping part is misinterpreted in the manufacturing process. There is also a large curve to change the defect, the cause of this kind of environment is caused by the stress of the thick material. There are also warpage defects, which can be ribs or faces. The reason for this kind of environment is that the gap force and the reaction force are not in a straight line, so that the moment occurs, or the gap of some molds is too large. There are many other achievements, such as positive and negative rebound defects, which have a certain impact on the quality and precision of the stamping parts, and some can not be reused, so advance the delivery process to find the rebound of the car stamping parts. The cause of the defect is very necessary.

Second, the impact of rebound status

(1) Automotive sheet metal material function

Within the elastic limit of the material, the greater the degree of deformation of the material, the higher the compliance limit, the greater the elastic modulus of the material, and the more the elastic deformation of the material, the greater the springback of the material. Larger, the softening of processing will be more serious. Assuming that the elastic modulus of the material is smaller, the degree of rebound in the process of processing will be smaller, and the ability to resist elastic deformation will be stronger.

(2) Bending center angle

The larger the value of the bending center angle is, the larger the rebound pile value is, and the more it will constitute a serious rebound phenomenon. The length of the stamping deformation increases with the increase of the bending center angle.

(3) Automobile sheet metal mold cavity gap environment

The mold is designed to leave a gap of material thickness in the inevitable working portion to accommodate the product in the gap. In order to complete the better activities of the material, the mold part of the mold should be discontinued after the end of the mold processing. Especially for bending the mold, the larger the gap of the working part is, the larger the rebound is. If the error of the thickness of the sheet allows the larger scale, the rebound will be larger, and the gap of the mold can not be achieved. Good must be.

(4) must bend the radius

The value of the inevitable bending radius is proportional to the rebound value, so the larger the curvature of the stamping, the more difficult it is to bend.

(5) Overall shape

If the shape of the whole machine is different, the rebound of the stamping part may be different. When the bending part is made in one bending, the stamping of each part of the stamping part during the forming process and the friction between the mold and the material will change the stamping. The stress condition of each part of the piece, so that the amount of rebound changes.

(6) Molding process

The forming process of the stamping part is a serious aspect that restricts the rebound value. Generally speaking, the rebounding result of the correction bending is better than the bending of the leisure. Assuming that an abnormal machining result is reached during the delivery of the same batch of stampings, the bending force necessary for correcting the bending is much larger than that required for the bending of the blank, so that the two methods adopt an abnormal bending force, and the result of the end arrival is also different. The larger the correction force necessary for the correction of the bending is, the smaller the rebound of the stamping part is. The correction of the bending force causes the outer fibers in the deformation zone to be elongated to reach the molding result. After the bending force is unloaded, the fibers on the inner and outer sides are stretched, but the rebound of the inner and outer sides is the same, so that the outward rebound of the stamping part can be reduced to a certain extent.

Other methods using cold stamping can process some harder materials, and steel and steel strips that are often used in the car sector can be processed using this equipment. Nowadays, when making car stamping parts, less and less steel is used. On the one hand, some aluminum and carbon materials have stronger hardness, and the use of this composite material can effectively reduce the car itself. The weight of the car has a very important effect on the consumption of less gasoline and diesel in the car. And with this new composite material, the protection of the car body is also more simplified.

Others in the use of this cold stamping technology to make car stamping parts, the quality of the product must be severely treated. Assume that when using this technology to make stamping parts, the production is not carried out according to the requirements, and the workmanship in the production does not meet the standard. The stamped parts produced in this way may be unqualified in some aspects, and the service life may be shortened in operation. And it is also simple to make the car dangerous in the course of travel, hurting the industry of the occupants in the car may be lost. Other hypotheses that produce unqualified products can create unnecessary waste for human resources.

Therefore, in selecting the materials and processing operations for these automotive stamping parts, it is not only necessary to carefully select the raw materials used in the processing of these automotive stamping parts, but also in the process of processing, it is also necessary to formulate a severe treatment system, at the time of inspection. Also, implement relevant inspection rules. This controls the quality of the middleware from the source.