Cold stamping dies are made of several common materials
(1) Carbon tool steel
T7A is a high-toughness carbon tool steel, which has high strength and toughness, and is suitable for making small molds that are easy to brittle or molds that bear large impact loads; T10A is the most commonly used steel, is a representative carbon tool steel with good performance, wear resistance is also high, after appropriate heat treatment can obtain higher strength and a certain toughness, suitable for the production of high wear resistance and bear less impact load of the mold. T8A has excellent hardenability, toughness, and high wear resistance, and is suitable for making small stretching and extrusion dies.
(2) Low-alloy tool steel
Low-alloy tool steel is based on carbon tool steel with an appropriate amount of alloying elements. In this way, the quenching cooling rate can be reduced, the thermal stress and microstructure stress can be reduced, the quenching deformation and cracking tendency can be reduced, and the hardenability of the steel can also be significantly improved
Edit the search image
Please click here to enter a description of the image (maximum 18 words)
The low-alloy steels used to make molds are Crwmn, 9MN2V, 9SICR, 9CRWMN, 9MN2, 7CRSIMNMOV, 6CRNIMNSIMOV, etc. CRWMN steel has good hardenability and small quenching deformation, but its wear resistance, toughness and deformation requirements still cannot meet the needs of cold work dies with complex shapes.
(3) High-carbon and high-chromium cold-work die steel
High-carbon and high-chromium cold work die steels include CR12, CR12MOV, and CR12MO1V1 which have the advantages of high hardness, high strength, high wear resistance, easy hardening, high stability, high compressive strength and small quenching deformation. The hardness of the blank after forging is higher and the internal stress is greater, so it must be annealed. During the tempering process of high-carbon and high-chromium steels, martensitic decomposition, carbide aggregation and residual austenite transformation will occur. In industrial production, 2~3 times of tempering are often used to improve the toughness of the previous tempering residual austenite into primary martensite, so as to improve the toughness of steel. CR12 steel has high strength and wear resistance, but its carbide inhomogeneity is more serious, and the brittle breaking tendency is great in use, and the toughness is low. For molds with higher requirements for comprehensive mechanical properties, the commonly used alternative steel grade is high-speed steel.
Edit the search image
(4) High-speed steel
High-speed steel has high hardness, compressive strength and wear resistance, and the use of low-temperature quenching, rapid heating and other technological measures can effectively improve its toughness. Therefore, high-speed steel is increasingly used in cold work dies that require heavy loads and long service life. High speed steel alloy has high element content, high price, poor process performance and high brittleness, which makes its application limited to a certain extent. Tungsten and molybdenum high-speed steel is widely used because of its uniform carbide distribution, fine particles, and the toughness of W6MO5CR4V2 steel is better than that of W18CR4V steel. The high-speed steel 6W6MO5CR4V, which has high strength and toughness, carbon reduction and vanadium reduction, has significantly improved its flexural strength, plasticity and impact toughness due to the appropriate reduction of carbon and vanadium content, while the hardness and secondary hardening ability are maintained.
Edit the search image
(5) Matrix steel
The matrix steels commonly used in the mold are 6CR4W3MO2VNB, 7CR7MO2V2SI, 5CR4MO3SIMNVAL, etc. Matrix steel is widely used in the manufacture of cold extrusion, thick plate cold stamping and cold heading and other molds, especially suitable for the manufacture of large and complex molds for difficult to deform materials, and can also be used as hot extrusion dies for ferrous metals, which is a kind of die steel that is used both hot and cold. With the widespread use of high-speed multi-station automatic cold heading machine, as well as the wide application of high-strength steel and high-toughness stainless steel stamping parts, the service conditions of cold stamping dies are more severe, and the use of electroslag remelting and composite strengthening of 012AL matrix steel cold stamping dies can significantly improve the service life.