What is metal stamping?
Metal stamping is a manufacturing process that uses one metal stamping die or a series of metal stamping dies to form a metal plate into a workpiece of three-dimensional size and shape.
Metal stamping products are used in various industries, such as automobiles and household appliances.
Automobile stamping parts are an important part of metal stamping industry.
Metal stamping can form sheet metal very efficiently.
The metal stamping die is installed on the press, and each stroke of the press forms a workpiece.
The production of metal stamping is completed by metal stamping workers.
Metal stamping dies are produced by machine tools or die factories.
Some machine tools and die factories also produce stamping parts.
Stamping production relies on molds and presses to complete the processing process.
Compared with other processing methods, it has the following technical and economic characteristics:
(1) The dimensional accuracy of stamping parts is guaranteed by the mold, which has the same characteristics, so the quality is stable and the interchangeability is good.
(2) Because of the use of mold processing, parts with thin walls, light weight, good rigidity, high surface quality and complex shapes that cannot or are difficult to manufacture by other processing methods can be obtained.
(3) Stamping generally does not need to heat the blank, nor does it cut a large amount of metal like cutting, so it not only saves energy, but also saves metal.
(4) Ordinary presses can produce dozens of pieces per minute, while high-speed presses can produce hundreds of thousands of pieces per minute.
So it is an efficient processing method.
Because the stamping process has the above prominent characteristics, it is widely used in all fields of the national economy.
For example, industries such as aerospace, machinery, electronic information, transportation, weapons, household appliances and light industry all have stamping processing.
Not only is it widely used in the industry, but everyone is directly connected with stamping products every day.
Stamping can be used to manufacture small precision parts in clocks, watches and instruments, as well as large cover parts for automobiles and tractors.
Ferrous metals, non-ferrous metals and some non-metallic materials can be used as stamping materials.
Related reading: Ferrous vs Non-ferrous Metals
Stamping also has some disadvantages, mainly manifested in noise and vibration during stamping.
These problems are not entirely caused by the stamping process and the die itself, but mainly caused by the backward traditional stamping equipment.
Advantages of stamping
Compared with other methods of mechanical processing and plastic processing, stamping processing has many unique advantages both in technology and economy.
The main performance is as follows.
(1) The stamping process has high production efficiency, convenient operation, and is easy to realize mechanization and automation.
This is because stamping is completed by stamping dies and stamping equipment.
The number of strokes of ordinary presses can reach dozens per minute, and the high-speed pressure can reach hundreds or even thousands per minute.
Moreover, each stamping stroke may get a punch.
(2) During stamping, because the die ensures the dimensional and shape accuracy of the stamping parts, and generally does not damage the surface quality of the stamping parts, and the life of the die is generally long, the stamping quality is stable, the interchangeability is good, and the characteristics of “identical”.
(3) Stamping can process parts with large size range and complex shape, such as stopwatches as small as clocks and watches, automobile longitudinal beams and covers, etc.
In addition, the cold deformation hardening effect of materials during stamping makes the stamping strength and stiffness higher.
(4) Stamping generally does not generate chips and debris, consumes less materials, and does not require other heating equipment, so it is a material saving and energy-saving processing method, and the cost of stamping parts is low.
The stamping process is becoming more and more mature, but it also has inevitable disadvantages while providing convenience:
① Mechanical press is widely used in stamping processing, with fast running speed and high strength in manual operation;
② The dies used in stamping are generally complex. Long manufacturing cycle and high cost;
③ Stamping processing must have corresponding molds, so it is most suitable for large batch production, and is limited to single piece and small batch production;
④ The design of stamping die emphasizes classical theory and experience, requires strong imagination and creativity, and requires higher requirements for the designer and manufacturer of the die.
Advantages and disadvantages of cold stamping and hot stamping
There are two ways to process metal stamping parts: cold stamping and hot stamping according to the temperature at the time of stamping.
Which processing method is reasonable depends on the strength, plasticity, thickness, deformation degree and equipment capacity of the material, as well as the original heat treatment state and final use conditions of the material.
Let’s understand the advantages and disadvantages of these two forming methods.
Cold stamping is a manufacturing process of metal workpiece at normal temperature.
It has the advantages of no heating, no oxide skin on the surface of stamping parts, good surface quality and low hardness;
The disadvantage is that there is hardening, and in serious cases, the metal will lose further deformation ability.
Cold stamping requires that the thickness of the blank is uniform and the fluctuation range is small, and the surface is bright and clean without spots and scratches.
Hot stamping is a stamping method that heats metal to a certain temperature range.
The advantages are that the internal stress can be eliminated to avoid hardening, the plasticity of the material can be increased, the deformation resistance can be reduced, the power consumption of the equipment can be reduced, and the hardness is high.
Its disadvantage is that there is oxide skin, which needs to be acid washed or shot peened. Because of its high hardness, it increases the difficulty of subsequent processing.
The cutting and drilling of subsequent processing need to be completed by laser technology.