Cold heading die - die steel selection and application
Low Alloy Cold Work Die Steel Cold Work Die Steel low-alloy main characteristics of a good technology, low temperature quenching, heat treatment of small deformation, strength and toughness, and wear resistance with the appropriate.
GD (6CrMnNiMoVSi) steel is a low alloy tool steel, is also typical of high strength and high toughness of cold work die steel, used to create easy edge collapse, a fracture of the Die, which have a higher life.
GD Steel Steel is the basis of CrWMn appropriate to reduce the carbon content in order to reduce carbide segregation, at the same time increase the nickel, wow, manganese, in order to increase the matrix strength and toughness, and a small amount of vanadium can clamp and grain refinement to improve the hardenability permeability and resistance to abrasion. And to increase the tempering stability, the role of chromium is to increase hardenability.
GD steel lath with more martensite, carbides less uniform and small, can be replaced by partial replacement of CrWMn steel and steel Cr12MoV cold mold, mold rarely use collapse and fracture toughness.
GD steel lath with more martensite, carbides less uniform and small, can be replaced by partial replacement of CrWMn steel and steel Cr12MoV cold mold, mold rarely use collapse and fracture toughness.
2, the matrix of steel steel substrate generally refers to its composition and high-speed steel hardening matrix organization the same chemical composition of steel.
If the 65Nb steel (65Cr4W3Mo2VNb), CG-2 steel (6Cr4Mo3Ni2WV) and so on. Steel substrate with a high-speed steel is the strength, red hardness, wear resistance and low-alloy steel with the toughness and plasticity, have been more widely used in the production of cold extrusion, cold plate thick red, cold forging dies, etc., especially suitable for deformation of materials difficult to use large and complex molds can be used for ferrous metal extrusion die of hyperthermia.
⑴ 65Nb steel for high-speed steel is W6Mo5Cr4V2 maternal, quenched in their matrix composition based on an appropriate increase in carbon content, and to carry out a small amount of niobium modified by alloying, the chemical composition shown in Table 1. Slightly higher than the carbon content of carbon matrix in order to increase the amount of time and improve the wear resistance of carbide, but also by adding a small amount of strong carbide forming elements Nb, to form a more stable carbide, to prevent quenching of the long grain heating large steel and to improve process performance.
If the 65Nb steel (65Cr4W3Mo2VNb), CG-2 steel (6Cr4Mo3Ni2WV) and so on. Steel substrate with a high-speed steel is the strength, red hardness, wear resistance and low-alloy steel with the toughness and plasticity, have been more widely used in the production of cold extrusion, cold plate thick red, cold forging dies, etc., especially suitable for deformation of materials difficult to use large and complex molds can be used for ferrous metal extrusion die of hyperthermia.
⑴ 65Nb steel for high-speed steel is W6Mo5Cr4V2 maternal, quenched in their matrix composition based on an appropriate increase in carbon content, and to carry out a small amount of niobium modified by alloying, the chemical composition shown in Table 1. Slightly higher than the carbon content of carbon matrix in order to increase the amount of time and improve the wear resistance of carbide, but also by adding a small amount of strong carbide forming elements Nb, to form a more stable carbide, to prevent quenching of the long grain heating large steel and to improve process performance.
65Nb steel is a high strength cold die steel, can be used to create complex, large or difficult to deformation of the cold metal extrusion die and the larger the impact load, as well as cold heading dies with Die, die, such as cold cut. 1080 ~ 1160 ℃ in the quenching heat to maintain the fine grain size, hardness and higher; in 1160 ℃ at heating quenching hardness highest 66.3HRC; Quenching in 1180 ℃ when growing up.
Therefore, it is most suited to recommend the use of quenching heating temperature 1080-1160 ℃. 1120 ℃ in quenching tempering ,500-540 ℃ at the time of the best mechanical properties.
Therefore, it is most suited to recommend the use of quenching heating temperature 1080-1160 ℃. 1120 ℃ in quenching tempering ,500-540 ℃ at the time of the best mechanical properties.
⑵ CG-2 steel is a combination of hot and cold steel of the substrate, the chemical composition shown in Table 1. Compared with the high-speed steel W6Mo5Cr4V2 slightly lower yield strength, the greater the squeeze pressure to bear the cold extrusion dies, select W6Mo5Cr4V2 high-speed steel production, a higher life; squeezing pressure on the smaller bear, shape complex and require a higher toughness Cold Heading Dies, select the CG-2 steel.
3. Tips to use materials directly affect the chemical composition and properties of materials, thereby affecting the service life of molds. In the actual production, should be a reasonable choice under the circumstances.
CrWMn of hardenability GCr15 than good, commonly used in the shape of complex, high-precision die a good wear resistance. However, after forging steel CrWMn more stringent control of cooling rate and using the appropriate heat treatment, to prevent mold in use edge collapse and cracking.
3. Tips to use materials directly affect the chemical composition and properties of materials, thereby affecting the service life of molds. In the actual production, should be a reasonable choice under the circumstances.
CrWMn of hardenability GCr15 than good, commonly used in the shape of complex, high-precision die a good wear resistance. However, after forging steel CrWMn more stringent control of cooling rate and using the appropriate heat treatment, to prevent mold in use edge collapse and cracking.
Cr12MoV steel with high wear resistance, but more serious carbide segregation, leading to the deformation direction and the lower strength and toughness. Cr12MoV compared to steel, GD steel production mold life improvement of varying degrees.
W6Mo5Cr4V2 and W18 Cr4V with high wear resistance and strength, commonly used in the production of extrusion pressure to bear a larger cold extrusion dies, but its toughness can not meet the complexity of the impact of large-scale and large mold load needs. Under pressure on smaller </ p>
? Shape complex, and require a higher toughness of the cold upsetting die, you can choose to use CG-2 steel. GD steel lath with more martensite, carbides and small, even less, you can replace the partial replacement of CrWMn steel and cold work die steel Cr12MoV.
LD steel eutectic carbide is much lower than Cr12MoV steel, hardenability than Cr12MoV high. GM steel Cr12MoV bending strength is much higher than steel, has a high hardness and toughness.
GM steel Cr12MoV than the carrying capacity of steel is much higher, can be replaced by large-scale production of Cr12MoV cold heading steel mold.
W6Mo5Cr4V2 and W18 Cr4V with high wear resistance and strength, commonly used in the production of extrusion pressure to bear a larger cold extrusion dies, but its toughness can not meet the complexity of the impact of large-scale and large mold load needs. Under pressure on smaller </ p>
? Shape complex, and require a higher toughness of the cold upsetting die, you can choose to use CG-2 steel. GD steel lath with more martensite, carbides and small, even less, you can replace the partial replacement of CrWMn steel and cold work die steel Cr12MoV.
LD steel eutectic carbide is much lower than Cr12MoV steel, hardenability than Cr12MoV high. GM steel Cr12MoV bending strength is much higher than steel, has a high hardness and toughness.
GM steel Cr12MoV than the carrying capacity of steel is much higher, can be replaced by large-scale production of Cr12MoV cold heading steel mold.