SU985084A1 - Method of heat treating of articles from austenite iron-nickel alloys with athermic kinetics of martensite conversions - Google Patents

Description

398508i | 4

ISO and H31 and Mn is - (8) - „stabilization, and directly

- () and does not lead to a noticeable phase hardening (grinding blocks

hardening of austenite. and an increase in the density of dislocations)

The purpose of the invention - stabilization leads to its hardening,

product dimensions due to stabilization-5 The proposed method of thermo-shaping of austenite with simultaneous packing was used to stabilize

Handling of products from le-Ni alloy H32.8 (32.8 wt.% Ni;

with athermal kinetics Marten-0.02 wt. % WITH; the rest of the iron;

sieve conversion. ; Mn. ,)

In order to achieve a set of athermal kinetics

whether in the known method of thermal-martensitic transformation,

What processing of products from austenite-After quenching steel samples H32,8

iron-nickel alloys with ather-cooled in liquid nitrogen below Mn

kinetics of martensitic one minimum possible maturation in the data, including quenching, the temperature of –19b С, with the aim of

cold treatment and aging are carried out most fully by athermipa Aq 160.. during 10-cc-d-s / martensitic transformations 20 min. neither In this case, 501 marten is formed when the product is cooled below Mnsite. Then the samples are heated to spreading - - about martensitic, 20 individual aging temperatures, retraction, and with subsequent heating above Ac (50, 500, 550, 600, and up to aging temperature, 650, 700, 750, 800, 850,) and goes completely into austenite. The solution is kept at these temperatures as a result of aging of the phase-riveted 15 min. The most severe effect of staustenitic (T 600-650 C; 10-20 min) 25 bilization manifests itself after old processes are established at 600 and (see table), neither the closest order nor the occurrence of Polon is shown in the regions of the concentration inhibition of the Mn of the alloy H32.8 directly homogeneous, which leads to it: but after quenching.

Type of processing alloy H32.8Mn, C iMn, C

Hardening (T 1100 ° C, min.) .- 105

Hardening + cooling to -196 0 + aging (, min) -92 + 13

Hardening + cooling to -19b C + aging (T 500 ° C, D 15 min) -118-13

Zaka + cooling to -19b ° С 4-aging (T 550 ° С, T 15 min)

Hardening + cooling to -V96 ° C + aging (T 600 ° C, D 15 min)

Hardening + cooling to -19b ° С + aging (, T 15 min)

Hardening -I- cooling to + aging (T 700 ° C, ir 15 min) -137-32

Hardening H cooling to -19b ° С + aging (T 750s, p. 15 min) -129-2

Hardening + cooling to -19b ° C + aging (T 800 ° C, D 15 min) -12 -19

Hardening + cooling to -19b ° С + aging (T 850 ° C, L 15 min) -116 -11 Hardening cooling to - maximum (T 900 ° C, t 15 min) -113 -8

A study is conducted on holding less than 10 minutes only weakening 32, 8, processed and otherwise. modes. Extracts of specimens quenched and cooled to -196 ° C. As a result of cold treatment at the same temperatures of old- 5 at -196 C aging at 600 ° C.

reni (..., 900С) during leaks and (min) increased

The effect of 20, 60, 80 min did not lead to the strength of austenite alloy H32.8.

Claims (3)

enhance stabilization of austenite, for the hardened state. b 230 MPa, and after processing according to the Nm I5 modes and. MPa Using the proposed method of heat treatment of products made of austenitic iron-nickel steels with athermal kinetics of martensitic transformation provides, in comparison with the known method, a significant increase in stabilization of austenite, expressed in an increase in the absolute value of DMN by a factor of k the possibility of simultaneous hardening of austenite while stabilizing the size of products; convenience of the method, expressed in the ability to carry out aging through almost any arbitrarily long period of time after the operation of cold treatment; reduction of time and energy costs. . The invention of the method of heat treatment of products from austenitic iron-nickel alloys with athermal kinetics of margensite transformation, including quenching, cold treatment below Mn, and with the aim of stabilizing the dimensions of the products and their strengthening / aging is carried out at a temperature of Ac 160-210 ° C for 1020 minutes. Sources of information taken into account in the examination 1. Butakova E.D. Malyshev K.A. The effect of external influences on the kinetics of martensitic transformations. F.M.M., 1973, t. 35.. 2, s. 398. 2. Georgieva I. Ya. Nikitina I.I. Isothermal and athermal transformations. Mitom, 1972, p. 5, 68. 3. Maximova 0. P. Nemirovsky V.V. On the nucleation of martensite in Fe-Nl alloys with explosive kinetics of martensitic transformation. D. A. N. USSR, 1967, vol. 177, No. 1, p. 31. A. Zhuravlev, L. G. et al. Effect of phase hardening on the isothermal and athermal martensitic transformation. F.M.M., 1973, Vol. 36, TOP 1, p. 109.