High-end ultra-precision die-cutting research and development

I. Principle of ultra-precision blanking

Ultra-precision punching technology is a stamping process with a small gap under strong pressure on the edge of the workpiece on the basis of ordinary punching. The principle is that the shaped ring on the guiding platen is pressed into the metal plate near the edge of the concave die, and then the punching force is applied to the plate under counter pressure, so that the material inside the edge is squeezed into the cavity of the concave die under three-way compressive stress, thus forming ultra-high-precision stamped parts.

II. Advantages of ultra-precision blanking

(1) The section is pure shear separation under three-way compressive stress, and the stamping equipment simultaneously improves the main stamping, pressing material and top part force in three directions.

(2) The die is manufactured with high precision and very small clearance, and a high precision ball guide is used.

(3) Small rounded corners on the die or die edge to allow more material to be squeezed into the deformation zone to increase the compressive stress.

(4) The blanking process requires high precision of equipment, die structure, material and performance of stamping oil.

III. Disadvantages of ultra-precision blanking

(1) The input of fine blanking machine is higher, more than ten times than that of ordinary presses.

(2) The specialization of fine blanking machine is strong, and it is not suitable for multi-species and small batch process, and it is feasible only after the batch reaches a certain scale.

(3) Fine blanking technology is a newer and more complicated technology, which requires not only advanced fine blanking machines, but also many advanced supporting equipments.

Fourth, the factors affecting the quality of punching parts

(1)The plasticity of pure metal blanking parts raw materials is better than alloy, impurity elements usually cause brittleness and reduce plasticity, and various alloys have different effects on plasticity.

(2) the organization of the metal of the blanking parts, single-phase organization is better than multi-phase organization plasticity, the nature of the second phase, shape, size, number and distribution state of the different.

(3) Process deformation temperature, as the temperature increases during the punching process plasticity increases, but this increase is not simply a linear rise.

(4) The increase in strain rate, both the side that makes the metal plasticity decrease and the side that makes the metal plasticity increase, the result of the combined effect of these two factors ultimately determines the change in metal plasticity.

(5) Deformation mechanical conditions, the more the number of compressive stresses in the main stress state, the larger the value, the better the plasticity of the metal.

V. Selection of supporting stamping oil

The factors that affect the efficiency of punching accuracy include the accuracy of stamping equipment, the rationality of die design, the quality of stamping dies, and the performance of stamping oil, etc. How to choose stamping oil is also an important issue in stamping technology:

(1) Silicon steel plate: Silicon steel plate is an easy material to punch and cut. Generally, low viscosity stamping oil is used for the sake of easy cleaning of the finished workpiece and on the premise of preventing the generation of punching burrs.

(2) Carbon steel plate: The first thing that should be noted when choosing stamping oil for carbon steel plate stamping is the viscosity of the drawing oil. The better viscosity is decided according to the difficulty of processing and the method of giving drawing oil and degreasing conditions.

(3) Galvanized steel plate: Galvanized steel plate is the welded steel plate with hot dip plating or electro galvanized layer on the surface. When choosing stamping oil, attention should be paid to the problem of white rust that may occur with chlorine type stamping oil, while using Yida Bo-rinsing sulfur type stamping oil can avoid the problem of rust, but the stamping oil should be degreased as early as possible after stamping process.

(4) Copper and aluminum alloy plate: Because copper and aluminum alloy have better ductility, so when choosing stamping oil, you can choose stamping oil containing oily agent and good sliding property, and avoid using stamping oil containing chlorine-type additive, otherwise the stamping oil will corrode copper and aluminum alloy and make their surface black.

(5) Stainless steel: Stainless steel is a material prone to process hardening, which requires the use of drawing oil with high oil film strength and good sinter resistance. Generally use stamping oil containing sulfur and chlorine compound additives to ensure extreme pressure processing performance while avoiding burrs and rupture of the workpiece.