Study on the Static Recrystallization Behavior of Thermal Deformation of Austenitic Stainless Steel for Nuclear Power

Dual-interval compression test was carried out with Gleeble-1500D thermal simulation testing machine on the 304 austenitic stainless steel used for nuclear power. The first-interval strain was 0.3, and the second 0.05, and the dual-interval strain rates is 0.1s-1, dual-interval temperatures of thermal deformation were 950°C, 1000°C, and 1050°C respectively. The softening behavior with thermal deformation at different temperatures and time intervals was studied. It was shown in the study that the occurrence of static softening was very easy for the material; the activation energy for static recrystallization Qrex was 383.45 kJ / mol in case of true strain of 0.3 and strain rate of 0.1s-1.

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Static Softening Behavior of Low Carbon High Niobium Microalloyed Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.990.36 ◽

2020 ◽

Vol 990 ◽

pp. 36-43

Author(s):

Dian Xiu Xia ◽

Heng Ke Du ◽

Xin En Zhang ◽

Xiu Cheng Li ◽

Ying Chao Pei

Keyword(s):

Deformation Temperature ◽

Static Recrystallization ◽

Microalloyed Steel ◽

Testing Machine ◽

Low Carbon ◽

High Deformation ◽

Softening Behavior ◽

Test Steel ◽

Static Softening ◽

Niobium Microalloyed Steel

The MMS-200 thermal simulation testing machine was used to study the static softening behavior of low carbon high niobium microalloyed steel. The effect of niobium to the static recrystallization softening behavior of the microalloy steel had been analyzed by establishing the kinetics model of static recrystallization and the micro-morphology of precipitates. The results indicated that: the static softening behavior of the tested steel significantly influenced by the deformation temperature and the interval pass time of the rolling processing. At relatively high deformation temperature and long interval pass time, the ratio of static softening was increased. Then the deformation temperature was lower to 950°C, and the static softening behavior of the test steel was ceased. But when the deformation temperature was higher than 1000°C, the static softening behavior of the test steel completely occurred. The activation energy of the test steel was 325·mol-1 by the established model calculated.

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Determination of Ratio of Yield Strength and Reduced Modulus during Cold Work Processing in 304 Austenitic Stainless Steel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.795.145 ◽

2019 ◽

Vol 795 ◽

pp. 145-151

Author(s):

Kai Li ◽

He Xue ◽

Kuan Zhao ◽

Shuai Wang ◽

Ting Wang ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Yield Strength ◽

Nuclear Power ◽

Cold Work ◽

Element Simulation ◽

Reduced Modulus ◽

Analysis Experiment ◽

304 Austenitic Stainless Steel ◽

Analytical Result

304 austenitic stainless steel is a common structural material used in the nuclear power plant, and its basic mechanical property would be changed by work hardening, which seriously affects the evaluation of the integrity of the nuclear power structure. The relationships of between the yield strength and the reduced modulus ratio (σ0.2/Er) with the residual indentation depth and maximum depth ratio (hr/hm) during cold work processing of 304 austenitic stainless steel is analyzed by using theoretical analysis, experiment and finite element simulation, and an approximate analytical model to expressσ0.2/Erbyhr/hmis established in this paper. The investigating results indicate that yield strength, Vickers hardness, andσ0.2/Erwill increase, andhr/hmdecreases with the material deformation increasing, and the analytical result of theσ0.2/Erbasically consistent with the experiment result.

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Effect of the Strain Reversal on the Microstructure and the Recrystallization Kinetics of the Austenite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.467-470.275 ◽

2004 ◽

Vol 467-470 ◽

pp. 275-280 ◽

Cited By ~ 3

Author(s):

D. Jorge-Badiola ◽

Amaia Iza-Mendia ◽

Isabel Gutiérrez

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Static Recrystallization ◽

Microalloyed Steel ◽

Hot Working ◽

Recrystallization Kinetics ◽

Static Softening ◽

Nb Microalloyed Steel ◽

Strain Reversal ◽

Kinetics Of

It has been demonstrated recently that when a reversion of the strain is applied during the hot working of a Nb-microalloyed steel, the subsequent static recrystallization kinetics is significantly affected. However, depending on the magnitude of the reversion, the static softening kinetics can be accelerated or delayed. This relates to the substructure dissolution taking place by the effect of the reversal. In the present work, new microstructural results obtained by EBSD on an austenitic stainless steel hot deformed by torsion is used to explain better the observed effect of the reversion of the strain.

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