SU943305A1 - Method for making tools - Google Patents

Description

one

The invention relates to mechanical engineering, in particular, to methods for the manufacture of products with stress-strain hardening.

Known manufacturing methods

products, including heating the billet to 930 - 1180 ° C, plastic deformation by extrusion with a degree of reduction of 25 - 75, podstuzhivanie, hardening, tempering and mechanical treatment, HP.

The closest to the invention to the technical essence and the achieved effect is a method that includes heating the workpiece to a temperature of 5, the dynamic stability of austenite, plastic deformation, quenching, high-temperature tempering, mechanical treatment, reheating to austenization temperature, 20 quenching and T-2 tempering.

The disadvantages of the known methods include low resistance under cyclic compression; low prosh-

bending, low workability due to the need to perform machining with a hardness greater than IRC 50; cracking in the manufacture of products made of high carbon and alloyed tool steels due to hardening after deformation.

The purpose of the invention is to improve the accuracy of the tool.

Claims (2)

The goal is achieved by the fact that in the method including heating the workpiece to austenization temperature, plastic deformation, quenching, tempering, machining, re-austenitizing, quenching and tempering, the deformation is carried out by extrusion and simultaneous multiple bending with a constant section of the workpiece, and before machining tempering is performed at a temperature from above Ac to below Ac, followed by accelerated cooling. The drawing is a diagram explaining the proposed method. The effect is achieved as a result of uniform deformation by angular displacement along the length of the workpiece and subsequent heat treatment, which by creating an equiaxial, directional and fine-grained structure, can improve the resistance of the material to bending fracture, including cyclic compression. Pushing the workpiece through the matrix at an angle with a constant cross section in the directions provides a more complete increase in the uniformity of deformation by angular displacements over the cross section, since the angular displacements are caused by the velocity difference in the direction perpendicular to the displacement. The angle between the direction of extrusion of the workpiece at a constant cross section and the axis of loading to ensure maximum deformations of the angle. by displacements across the section without gaps along the length of the workpiece is selected from 0 to 80 °. The proposed method is carried out as follows. The billet 1 is heated to the thermodynamic stability temperature of austenite (930 - 1200 C), forced to a temperature 1bO — above Agz, and pushed through the cavity of matrix 2 smoothly at an angle to the axis of force loading in directions x with a constant cross section. The punching is carried out by the punch 3 and the liner k, for example, of compressed graphite installed at the end of the workpiece 1. After deformation, the workpiece 1 is hardened, heated to a temperature from above AO) to below Ac, it is annealed within the course of primary recrystallization, rapidly cooled , for example, in air and mechanical. | processing tools are made. It is then reheated to the austenization temperature, quenched, and tempted. The working cavity of the matrix 2 along the entire length is made with a section equal to the section of the workpiece 1. In the stamp, the matrix 2 is mounted in the container 5, and the punch 3 is fixed on the plate 6 by the holder 7. Example. In the manufacture of a punch from steel X12M for cold extrusion of the stem of the pusher motor valve D-240, the billet 0 30x80 mm is heated to, pressed in the air before and pushed through the cavity 0 30 mm matrix at an angle b5 to the axis of force loading in 2 directions without changing section. After deformation, it is quenched in oil (50 ° C), heated to 720 ° C, annealed for kO min, cooled in air, and made into a punch by turning. Then heated to 1025С and quenched, in oil at 60 ° С. Vacation is made at 200 ° C for 2 hours. The impact strength of the material of the punches made according to the proposed method is QH 0.37 - O.Z MJ / m and the bending strength of 6 and 3 G. 3350 - 3150 MN / m, and in the production according to the opposable is (it, g 2800 2600 MN / m and RN 0.29 - 0.27 MJ / m. The durability of the punches increases by 20 - 30 thousand, cycles. Thus, increasing the strength of the material of punches by 18-22%. Using the proposed method provides increased durability under cyclic force compression by 30 and material strength by 18-22%, in addition, the technological capabilities of thermal-strain hardening are expanded. heating billet and up to the austenization temperature, plastic deformation, quenching and tempering, characterized in that, in order to increase durability, deformation is carried out by extrusion with simultaneous multiple bending with a constant cross section of the workpiece, and tempering before machining is performed at a temperature of 20 ° C above Ac., up to 50 ° C below Ac, followed by accelerated cooling Sources of information taken into account in the examination J. Manufacturing of parts by plastic deformation. Ed. KN "Bogo Vlensky and others. L., 1975, p. 165-166. 2. Novikov N.N. Theory of heat treatment of metals. M., 1978, p. 356-358.