SU1077674A1 - Method of producing blank from the alloy on iron-nickel base - Google Patents

Abstract

A METHOD FOR OBTAINING A PLANT FROM AN ALLOY ON A IRON NICKEL BASE, including heating and rolling the ingot in two perpendicular directions, characterized in that, in order to increase the quality of the workpiece and increase productivity, the ingot is heated at 1150 - 10 - 14 h with subsequent rolling in from the direction of the required size with cytuap compression for each side of the ingot 65 - 85% with single o x 6 - 19% and finish rolling at a temperature not lower than 990 C.

Description

 sl

The invention relates to rolling production, in particular to the production of a billet of a precision alloy on an iron-nickel base from ingots of large mass.

There is a known method of obtaining ingots from an alloy on an iron-nickel base, in which an ingot is deformed by forging at several conversions into a square or flat piece. Taking into account the metal temperature drop of 50-70 ° C during the transportation of the ingot from the furnace to the hammer, heating is carried out to 1230-1250 ° C for 6-7 hours for ingots of 500 kg and 9-10 hours for ingots of 1000 kg ij.

The disadvantages of the known method of producing precision alloy blanks, for example, H52, 5CH, are low productivity due to forging ingots of low weight and poor surface quality due to the high heating temperature.

Closest to the present invention is a method for producing a billet of an alloy on an iron-nickel-cobalt base, including heating and rolling an ingot for several stages. According to this method, the ingot is heated at 1260-1300s for 15–20 hours and is rolled onto an intermediate section with a total compression on each side of 30–50% at a temperature at the end of rolling not lower than 1000–1050s. After this, the intermediate section roll is reheated at 1220-12 ° C for 10-12 hours and is finished rolling to the required size 2.

The disadvantage of this method of producing a blank is the poor quality of the blank, due to the formation of continuous deep defects on the surface caused by double and prolonged heating of the ingot, as well as a high heating temperature. In addition, the performance of the method is low, as it provides for a long cycle of processing the ingot for two redistribution.

The purpose of the invention is to improve the quality of the workpiece and increase productivity.

This goal is achieved by the fact that, according to the method of producing a tia alloy billet, an iron-based zoniekel base, comprising heating and rolling the ingot in two perpendicular directions, the ingot is heated at 1150-1190s for 10 14 hours followed by rolling in one of the directions to the required size with a total compression on each side of the ingot 65 - 85% with a single reduction x 6-19% and finish rolling at a temperature not 990 ° C.

The proposed method allows to obtain a high-quality billet of an alloy of iron-nickel base with high performance.

At temperatures above 1190s, iron-nickel base metals, for example 50N, are prone to significant mezero oxidation of the surface of the workpieces, which, due to plastic deformation, leads to cracking of the metal and macroscopic deformations of the roll stock, which require deep cleaning or cause rejection of the workpieces. When heated to a temperature below 1150 ° C, the temperature of the end of rolling in connection with the cooling of the ingot during transport to the mill and during the rolling process will be lower, which will lead to a decrease in ductility and, therefore, defects on the surface of the workpieces. In addition, rolling at low temperatures is difficult because of the high deformation forces.

With frequent rollbacks of less than 6%, there is a significant non-uniformity of deformation over the section of the ingot, contributing to the formation of surface defects and internal ruptures in the workpieces. With a reduction of more than 19%, the resistance to deformation increases sharply and the ingot is machined.

Rolling an ingot with a total strain of less than 65% leads to significant metal grain size and high anisotropy of properties. When rolling an ingot of an alloy on an iron-nickel base with a total reduction of more than 85%, the plastics stock of the metal has been exhausted due to the delayed recrystallization processes, which also contributes to the formation of defects and an increase in the resistance to deformation.

An example. To obtain a billet with a section of 135if5lO mm from an alloy on an iron-nickel base, for example, 5OH, an ingot weighing 4.5 tons with a maximum section of mm is heated to 12. h and the rolling is carried out to the required size in table 1 with a single crimp on each side 6-19 % and total compression in one of the directions 79%. The temperature at the end of rolling is 1020 C. The blanks obtained by the proposed method have a smooth macrostructure. Stripping depth 0.5-2 mm instead of 20 mm according to the requirements of TU 14-134-177-80 on a bond from a BON alloy. After selective cleaning, the workpiece is rolled onto a hot rolled rolled steel and then onto a cold rolled belt with 10-11 class of surface finish. Table 2 shows the results of testing the method for various options for heating and rolling ingots weighing 4.5 tons of 5OH alloy with a cross section and an assessment of the deformability of the blanks. In addition to improving the quality of the applied method, in comparison with the prototype, it reduces the cost of the limit and increases the productivity by reducing the processing cycle of the ingot by 2.0-2.5 times. In the proposed method, the performance is equal to g with uo-HUi Sp n pr where Q is the mass of the ingot; T.- cycle time, h; heating and rolling time. . I-JU Accepted that 1bp great -pr Qr Q, the performance of the proposed method is 2.2-2.5 times more. The economic effect from the use of the invention is 35.45 thousand rubles. at the following rates. Total production at the mill 1360,01368,4 Production of iron-nickel alloys 7,015.4 Specific fixed costs 5740 Table

12

3 4

Canting

6 00 M 7 5

5 6

Canting

7 8 9 380 "550.

0 11 12

6.9

1170 7.4 1168 8.0 1165 8.7 1160

9.1

1155 10 1150

1145

10.4 1140 11.6 1133 13.1 1125 15.1 1115 16.1 1105 19.0

6SO

123.0

14

50

65

1110

ten

Continued table. one

Table. 2

surface quality.

billets due to low ductility, high stress deformation forces, under-rolled

Violations of the surface continuity due to intergranular oxidation, variability of the macrostructure of the workpiece

High deformation forces 1230 14 85 1000 1150 8 85 970 1190 16 65 1060

10776748

Continued table. 2 Interruptions of the surface ire-ea inter-integer oxidation internal ruptures of the workpiece due to uneven deformation over the cross section Underheating of the lattice, high deformation forces, discontinuity due to low ductility Disruption of the surface of the workpiece due to intergranular oxidation

Claims (1)

754) METHOD OF PREPARING WORKING FROM ALLOY ON THE IRON-NICKEL BASIS, including heating and rolling the ingot in two perpendicular directions, characterized in that, in order to improve the quality of the workpiece and increase productivity, the ingot is heated at 1150 - 1190 ° C for 10 - 14 hours followed by rolling in one of the directions of the required size with a total compression of 65–85% on each side of the ingot with single reductions of 6–19% and finishing rolling at a temperature of at least 990 ° C.