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The surface and internal performance of precision hardware stamping parts materials have a significant impact on the quality of stamping products. The requirements for stamping materials by Licao Precision Mold are:

① The thickness is precise and uniform. The stamping mold is precise and has small gaps. Excessive thickness of the sheet metal can increase deformation force, cause material jamming, and even cause the concave mold to expand and crack; Thin sheet metal can affect the quality of the finished product and even cause cracking during deep drawing.

② The surface is smooth and clean, without spots, scars, scratches, surface cracks, etc. All surface defects will remain on the surface of the finished workpiece, and crack like defects may expand deeply and widely during bending, drawing, forming, and other processes, resulting in waste products.

③ The yield strength is uniform. During stamping processes such as deep drawing, flanging, and bulging, the occurrence of anisotropic yielding occurs in sequence, and the plastic deformation amount is inconsistent, which can cause uneven deformation and inaccurate forming, resulting in defective or scrap products.

④ High uniform elongation. In tensile testing, the elongation before the appearance of necking phenomenon in the sample is called the uniform elongation. During deep drawing, the deformation of any area of the sheet material should not exceed the uniform extension range of the material, otherwise uneven deformation may occur.

⑤ The yield strength ratio is low. The ratio of yield limit to strength limit of precision metal stamping parts is called yield strength ratio. A low yield to strength ratio can not only reduce deformation resistance, but also reduce the tendency to wrinkle during deep drawing, reduce the rebound amount after bending, and improve the accuracy of bent parts.

⑥ Low work hardening. The work hardening that occurs after cold deformation will increase the deformation resistance of the material, making it difficult to continue deformation. Therefore, low hardening index plates are generally used. However, materials with high hardening index have good plastic deformation stability and are less prone to localized tensile cracking.

In actual production, Licao precision molds often undergo process tests, such as deep drawing performance tests, bulging performance tests, etc., to verify the stamping performance of materials and ensure the quality of precision hardware stamping parts.