Japanese hot extrusion die steel developments

Japan, as the heat of the material between the extrusion tool most used SKD61 ~ SKD62. In addition to the aluminum extrusion rod SKD61, the strength and toughness necessary in the case of 18Ni maraging steel are also used. In the copper alloy or titanium alloy extrusion die in the Department of ZrO₂ ceramic mold to get a good report on the results. But generally the experience gained from the original hot-work tool steel in the context of the development of improved materials suitable for extrusion mold, then of course, application of heat between the stamping die materials and die-casting material of knowledge. HongChao(DongGuan)Mold & Technology Co., Ltd. The practical application shows the following types of hot work die steel is suitable for hot extrusion dies: QRO 90 SUPREME, DIEVAR (Uddeholm tool steel), 1.2367, DAC55, DAC40, DH31 -S, DH31-EX (Japan Daido steel), HD steel, Y4 Steel, GR Steel (domestic high heat hot die steel) and so on.
Squeeze the tool point is extrusion cylinder problem, break the mold and wear. In the extrusion cylinder required high temperature strength and fatigue strength, aluminum extrusion using an improved SKD7 or SKD61 hardenability, heat-resistant steel and so on. As the extrusion of copper alloy extrusion temperature is high, so use the A286 (SUH660) and other heat-resistant alloys, die from the angular position of the rupture and wear resistance is particularly required.
Aluminum extrusion is the original home or building with the main building, but in recent years, manned vehicles and trucks with increased demand for lightweight components, so large, complex shape components increased use. This extrusion die deflection increases, the Department of Burns and sliding wear of extrusion increased. SKD61 common tool steel from Japan, in order to prevent abrasion and burns mold, mold implementation of repeated nitrogen treatment. As a result, hardened and nitrided parts of the nitridation of the mold internal heating due to prolonged gradual softening, due to strength reduction and waste is inevitable. Therefore require the use of nitrogen does not soften even after repeated for a long time the anti-softening of the great material. For example, in high-Mo-W system with 4% Cr increase in resistance to tempering of the material (Hitachi Metals for the DAC40, etc.). However, the use of large mold, because lack of hardenability, so use an increased resistance to softening, while the high hardenability of the material, using the 5% Cr to strengthen the department of materials. In addition, because the cost of the thin wall of the mold, the mold there is increased tendency to rupture in such a mold in the development of 5% Cr-Si system taking into account the low toughness of the material and practical application.
In the copper alloy extrusion processing tool steel billet temperature rises to the A1 or A1 near the phase transition point above the phase transition point the extent of the mold material to be machined with a long contact time, so deep below the surface reduces the strength softening produced. To this end, in contact with the blank mold, Extrusion, extrusion pad, etc., generally used in more than 700 ℃ high temperature creep strength superior alternative to the original materials, martensitic steel SKD5 or SKD7. One of them is the Mn-Cr-V austenitic hot work die steel, but this steel is precipitated in the austenite matrix MC carbide precipitation hardening steel, cheaper than the superalloys, but the MC carbide precipitation in austenite grain boundaries, reducing the toughness and the poor are cutting their shortcomings.
Therefore, sulfur and other cutting elements added to replace part of the nickel-manganese, in particular, precipitation hardening element to add the partial use of improved materials. The material hardness of 40HRC or more precipitation hardening, and is not magnetic, so Plastic Magnet of stamping dies are also used. However, long-life copper extrusion tool is generally used superalloys. Alloy V-57 or Inconel718 and so on. One line of austenitic alloys (swelling) expansion coefficient, low thermal conductivity, considered suitable for pressing the sleeve with the use of materials, to prevent the extrusion quench pads, etc., can be used as a design or conditions of the response.

There, SKT4 general motif for extrusion molding, die support ring, SKD61 for mass production, aluminum extrusion with a mandrel, crush pad generally used SKD61 or SKD62.
In addition, the main body of the extrusion die for a high-strength materials, particularly the discussion. Lower than the temperature of 700 ℃ copper billets extruded brass sleeve around the application of superior creep strength than the SK8 0.1C-10Cr-Mo-V-Co system intermetallic compound precipitation hardening martensitic steel AFC-77.

More information
Please direct HongChao(DongGuan)Mold & Technology Co., Ltd. service contact (hotline 0769 -82621066 / 82621088, the National Service Hotline :400-699-1286) to get more information about Japanese hot extrusion die steel developments and high-quality mould steel (Japan Daido steel, Assab tool steel, Germany Groditz mould steel, Japan Fuji high-speed steel, Japan's Hitachi mould steel, etc.) the selection, application, heat treatment and inventory and other related information.
Source: HongChao(DongGuan)Mold & Technology Co., Ltd. Technology Center
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