SU1690939A1 - Radial swaging tool - Google Patents

Abstract

The invention relates to the processing of metals by pressure. The purpose of the invention is to improve the quality of forgings obtained by deformation on a radial crimping machine. The tool consists of two mutually perpendicular pairs of strikers with two inclined lead-in and one horizontal calibrating areas. One of the two sloping portions of each striker has a shorter length than the other, within the following limits; L (0.6 ... 0.9) lk, where L is the length of the smaller inclined section of the striker, Ik is the length of the calibrating section of the striker. The mutual arrangement of the strikers is such that the lead-in part of the tool is formed by large inclined sections of one pair and smaller inclined sections of another. When the workpiece is radially compressed, the length of the lead-in area L is carried out by the unequal deformation of the metal by each pair of heads. This leads to the development of plastic deformation of the metal of the axial zone of the workpiece. 1 tab., 4 Il.

Description

The invention relates to the processing of metals by pressure and can be used in the manufacture of forgings from low-plastic alloy radial crimping machines.

The purpose of the invention is to improve the quality of forgings due to the intensification of deformation of the metal in the axial zone.

FIG. 1 and 2 show the arrangement of the strikers of two mutually perpendicular pairs 1 and 2; Fig, 3 is a graph of the results of the calculation of the accumulated deformation in the axial zone Aos 1 referred to the maximum accumulated deformation value along the cross section of the workpiece, I max; in fig. 4 is a graph of the results of calculating the degree of utilization of the plasticity resource of a metal in the axial zone of a cable,

The tool for radial reduction includes two inter-perpendicular pairs of dies with two inclined feed-in and one horizontal gage area. One of the two inclined sections of each striker has a shorter length than the other, which is within the following limits:

L (0.6 ... 0.9) lk,

where L is the length of the smaller lead-in portion of the striker;

Ik - the length of the calibrating section of the striker.

The mutual arrangement of the strikers is such that the lead-in part of the tool is formed by large inclined sections of one pair and smaller inclined sections of another.

ON

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about

The tool works as follows.

During the radial reduction with a decrease in the diameter of the workpiece, the metal is deformed in the lead-in area over a length p equal to

-o- fi angle of inclination

plots. In the event that the length of the lead-in portion L of one of the pairs of strikers is less than this value, each volume of the workpiece entering the zone of action of the tool is deformed in a stretch of length - under

exposure to only one pair of strikers.

Such application of external forces provides intensive plastic deformation of the metal in the axial zone. In addition, due to the broadening occurring at this stage, the billet acquires an oval shape and further deforming it with two pairs of strikers over the length of the lead-in area I. compression and, consequently, the development of plastic deformations. The smaller the value of L, the greater, at a constant 1p, the extent of the deformation section of the workpiece of one pair of dies and the larger the accumulated strain in the axial zone.

The factor directly influencing the distribution of plastic deformations across the section of the workpiece, the degree of utilization of plasticity resource, is the ratio of the length of the smaller lead-in section of the striker L to the working length of the lead-in section P. that we00 and v; oc are defined

faces

by attitude

From FIG. 3 it can be seen that, from the point of view of increasing accumulated deformation, the values of -r- do not exceed 0.9. When |

-j- less than 0.6 degree of use

The plasticity resource in the axial zone V oc, as can be seen from FIG. 4, exceeds 0.9, which, at a significance level of 1.0, can lead to the formation of defects in this zone. For low-plastic steels and alloys prone to defect formation, a typical representative of which is high-speed steel R6M5, it can be considered that the value of -: - j leads to substantially k

mu increase accumulated strain in

the axial zone without destruction is within 0.6 ... 0.9, i.e., L (0.6 ,,. 0.9) lk.

Example. 12 ingots with a diameter of 430 mm from high-speed steel R6M5 were subjected to deformation in four passes to

size 210 mm (with dimensions of intermediate blanks 370, 310 and 260 mm) on a radial crimping machine strikers with a calibration span of Ik 130 mm, an insertion angle of 8 ° and a lead-in length of one of the striker pairs of 220 mm and the other respectively 65, 80, 100, 115, 130 and 220 mm, i.e., with a L value of 0.5 lk, respectively; 0.6lk; 0.75 lk; 0.9lk, 1.01k and 1.71k (two ingots for each size L).

Then the ingots were deformed on a radial crimping machine in conventional die heads of a final size of 120 mm. After deformation, transverse templates were cut out from the obtained forgings to study the macrostructure, and microsections were made from the metal of the axial zone of the forgings to determine carbide heterogeneity. The results are presented in the table. Forgings deformed in the tool

with a length of the smaller lead-in area L 1.7 Ik 220 mm (approximately equal to the working length of the lead-in area 214 mm), in the axial zone there was a coarse, almost undeformed carbide mesh. For L 0.5 ... 0.9lk, the structure of the metadla of the axial zone satisfied la of the requirements of GOST 19265-73 for the carbide heterogeneity of high-speed steel bars, however, a study of the macrostructure showed that with L 0.5lk 65 mm in

the axial zone is observed destruction of the metal in the form of cracks,

The results of metallographic studies are presented in the table.

Used tool with its

sufficient simplicity allows to improve the development of the axial zone of the original billet and thereby improve the uniformity of the structure and technical properties over the cross section of the forging.

Claims (1)

The invention The tool for radial reduction, containing two strikers of strikers arranged with the possibility of oncoming movement in two mutually perpendicular planes, each of which is made with inlet and parallel to its axis calibrating sections, characterized in that improving the quality of forgings due to the intensification of metal deformation in the axial zone, one of the two inclined sections of each striker has a smaller length compared to the other within the following limits: L (0.6 ... 0.9) lk, where L is the length of the smaller lead-in portion of the striker; Ik is the length of the calibrating section of the striker, the lead-in part of the instrument being formed by large inclined sections of one pair and smaller inclined sections of the other. The results of metallographic studies Phie.1 FIG. Z O 0.1 0.2 0.3 TO 0.5 US Q7 0.8 QJ9 1.0 V /, 2 1.3 1, C Phage h Aa About 0.1 0.2 0.3 and 0.5 0.6 0.7 03 0.9 W V P 13 /.Ґ T FIG H