The choice of cold extrusion die materials, cold extrusion die working conditions and performance requirements

According to the extruded metal flow direction and the relationship between the direction of movement of the extrusion die, cold extrusion head can be divided into direct extrusion, reverse extrusion and composite extrusion three.

①Working conditions. Cold extrusion dies are designed for heavy-duty applications. The compressive stress on the punch can be up to 2500 MPa for mild steel with a backpressure tensile strength of 400 MPa, and higher deformation resistance when extruding low alloy steel, tempered steel or stainless steel.

② Performance requirements As the die is subjected to great extrusion pressure in the extrusion process, the die material must have high compressive and flexural strength, as well as high toughness and wear resistance. General hardness should reach 61 ^-63 HRC; in addition, the die material must also have high temperature resistance and thermal fatigue resistance.

(2) the choice of cold extrusion materials

Different extrusion materials have different deformation resistance and different die material requirements. TIOA, CCWMn, 60Si2Mn, Cr12 steel, W18Cr4V, W6Mo5Cr4V2 and new die steel can be used as cold extrusion die materials. The most commonly used steel grades in the factory at present are 60Si2Mn, Cr12, CY12MOIV1, M, GM, EB5, LD, 65N6, 012A1, LMl, LW2, GD steel, maraging steel and hard alloy.