Introduce in detail: the processing technology of precision stamping parts

Precision stamping parts processing is a process of applying pressure to metal plates through dies to make them plastically deform or separate, so as to obtain high-precision and high-consistency parts. Its core features are high efficiency, high precision and low cost, and it is widely used in the fields of electronics, automobiles, medical devices and so on.

First, the core process

Precision stamping should follow a strict sequence of steps to ensure the accuracy of parts and production stability. The main process is as follows:

Raw material preparation

Select metal plates that meet the requirements (such as stainless steel, copper, aluminum, cold-rolled steel, etc.), and cut them into "strips" or "blanks" with fixed specifications according to the size of the parts. At the same time, it is necessary to check the thickness, hardness and surface smoothness of the raw materials to avoid affecting the subsequent processing.

Mold design and manufacture

This is the core link of precision stamping. The mold should be designed according to 3D drawings of parts, including punch (punch), concave die, positioning device, discharging device and other parts, and the accuracy of the mold should be higher than that of parts (usually up to ±0.005mm). The common mold materials are high-speed steel and cemented carbide to ensure wear resistance and service life.

punch forming

The prepared raw materials are sent to a punching machine (such as a high-speed punching machine and a precision hydraulic punching machine), and the processing is completed by closing and separating the mold. The common working procedures include:

Blanking/punching: separating plates to obtain the shape or hole position of parts, such as screw hole processing of mobile phone shell.

Bending: Bending a plate at a specified angle along a specified axis, such as the pins of an electronic component.

Stretching: pressing a flat plate into a hollow part (such as a battery case), the stretching coefficient should be controlled to avoid material fracture.

Flanging: punching the hole or edge of the part to form a raised cylinder or edge to enhance the structural strength.

Subsequent treatment

After stamping, the parts need to go through auxiliary processes to optimize their performance. The common steps include:

Deburring/chamfering: By grinding, polishing or electrochemical treatment, the edge burr generated by stamping is removed to avoid scratching or affecting assembly.

Surface treatment: zinc plating, nickel plating, chromium plating, painting, etc. are carried out as required to improve the rust resistance, conductivity or aesthetics of the parts.

Inspection: use precision instruments (such as two-dimensional imager and three-coordinate measuring instrument) to inspect the size and shape tolerance of the parts to ensure that they meet the requirements of the drawings.

Second, the key process characteristics

The core advantages of precision stamping, which are different from ordinary stamping, are embodied in the following three aspects:

High precision control

Depending on the high-precision punch (positioning accuracy of ±0.001mm) and precision die, the dimensional tolerance of parts can be controlled within ±0.01mm, and the form and position tolerance (such as flatness and verticality) can meet the IT5-IT7 standard, which is suitable for parts with extremely high accuracy requirements (such as 5G communication components).

High production efficiency

The high-speed punch can complete hundreds of punching cycles per minute, and with the automatic feeding and receiving system, continuous batch production can be realized, and the daily average production capacity of a single production line can reach tens of thousands, greatly reducing the cost of unit parts.

High material utilization rate

By optimizing the layout design (such as nested typesetting), the waste of raw materials is reduced, and the material utilization rate can usually reach 80%-95%, which is especially suitable for the processing of precious metals (such as copper and silver) and reduces the production cost.

Third, the applicable scenarios and limitations

Applicable scenario

Material: suitable for metal plates with a thickness of 0.05-3mm (such as stainless steel, aluminum, copper alloy).

Type of parts: parts with large quantities and relatively regular structures, such as connector terminals, automobile sensor housings, and medical device accessories.

limitations

Not suitable for thick plates (usually > 3 mm) or high-hardness materials (such as hardened steel), which may easily lead to mold wear or parts cracking.

Complex special-shaped parts (such as multi-curved surfaces and deep cavity structures) may need multiple sets of molds to be processed step by step, and the initial mold investment cost is high.