Retained Austenite and Notch Toughness in Synthetic HAZ of 9% Ni Steel: —Studies on Retained Austenite in Cryogenic Steel Welds (Report 2)—

Hiroshi Tamura, Tadao Onzawa, Susumu Uematsu

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

The effect of retained austenite on notch toughness in HAZ of 9% nickel steel welds had been discussed in author's previous paper. In this paper, the above correlation and factors affecting on the formation of retained austenite during weld process were investigated in more detail by using the simulation technique. The obtained result indicated a noticeable effect of a peak temperature, in particular near 620°C being closer to ACCI temperature (about 630°C), of secondary thermal cycle, after primary thermal cycle 850 to 1350°C, on the amount of retained austenite, and however, there was a lesser effect of another factors, such as heating and cooling rates etc. on it. In the other hand, since the formation of globular austenite occured rapidly and abundantly during heating process in welding, as comparing the ordinary heat treatment, there was a variation in the amount of the retained austenite in very short time if holding at the peak temperature of tempering cycle. It was found that there was a fairly good correlation between the amount of retained austenite and toughness. When the grains, however, were remarkably coarsened by the primary thermal cycle similar to that near weld bond, the toughness was no longer improved regardless of the amount of retained austenite, unless the secondary thermal cycle being above 800°C. This secondary cycle resulted in the grain refinement and the formation of the enriched zone of alloying elements, where the stable austenite precipitated in 3rd thermal cycle, mainly, at prior austenite grain boundaries.

Original languageEnglish
Pages (from-to)854-860
Number of pages7
JournalJOURNAL OF THE JAPAN WELDING SOCIETY
Volume49
Issue number12
DOIs
Publication statusPublished - 1980 Jan 1
Externally publishedYes

Fingerprint

Steel
Austenite
Cryogenics
Toughness
Welds
Industrial heating
Grain refinement
Tempering
Heat affected zone
Alloying elements
Nickel
Temperature
Welding
Grain boundaries
Heat treatment
Hot Temperature
Cooling
Heating

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Surfaces, Coatings and Films
  • Metals and Alloys

Cite this

Retained Austenite and Notch Toughness in Synthetic HAZ of 9% Ni Steel : —Studies on Retained Austenite in Cryogenic Steel Welds (Report 2)—. / Tamura, Hiroshi; Onzawa, Tadao; Uematsu, Susumu.

In: JOURNAL OF THE JAPAN WELDING SOCIETY, Vol. 49, No. 12, 01.01.1980, p. 854-860.

Research output: Contribution to journalArticle

@article{5ef7316ed2554be1beb4d90c5763328b,
title = "Retained Austenite and Notch Toughness in Synthetic HAZ of 9{\%} Ni Steel: —Studies on Retained Austenite in Cryogenic Steel Welds (Report 2)—",
abstract = "The effect of retained austenite on notch toughness in HAZ of 9{\%} nickel steel welds had been discussed in author's previous paper. In this paper, the above correlation and factors affecting on the formation of retained austenite during weld process were investigated in more detail by using the simulation technique. The obtained result indicated a noticeable effect of a peak temperature, in particular near 620°C being closer to ACCI temperature (about 630°C), of secondary thermal cycle, after primary thermal cycle 850 to 1350°C, on the amount of retained austenite, and however, there was a lesser effect of another factors, such as heating and cooling rates etc. on it. In the other hand, since the formation of globular austenite occured rapidly and abundantly during heating process in welding, as comparing the ordinary heat treatment, there was a variation in the amount of the retained austenite in very short time if holding at the peak temperature of tempering cycle. It was found that there was a fairly good correlation between the amount of retained austenite and toughness. When the grains, however, were remarkably coarsened by the primary thermal cycle similar to that near weld bond, the toughness was no longer improved regardless of the amount of retained austenite, unless the secondary thermal cycle being above 800°C. This secondary cycle resulted in the grain refinement and the formation of the enriched zone of alloying elements, where the stable austenite precipitated in 3rd thermal cycle, mainly, at prior austenite grain boundaries.",
author = "Hiroshi Tamura and Tadao Onzawa and Susumu Uematsu",
year = "1980",
month = "1",
day = "1",
doi = "10.2207/qjjws1943.49.854",
language = "English",
volume = "49",
pages = "854--860",
journal = "Yosetsu Gakkai Shi/Journal of the Japan Welding Society",
issn = "0021-4787",
publisher = "Japan Welding Society",
number = "12",

}

TY - JOUR

T1 - Retained Austenite and Notch Toughness in Synthetic HAZ of 9% Ni Steel

T2 - —Studies on Retained Austenite in Cryogenic Steel Welds (Report 2)—

AU - Tamura, Hiroshi

AU - Onzawa, Tadao

AU - Uematsu, Susumu

PY - 1980/1/1

Y1 - 1980/1/1

N2 - The effect of retained austenite on notch toughness in HAZ of 9% nickel steel welds had been discussed in author's previous paper. In this paper, the above correlation and factors affecting on the formation of retained austenite during weld process were investigated in more detail by using the simulation technique. The obtained result indicated a noticeable effect of a peak temperature, in particular near 620°C being closer to ACCI temperature (about 630°C), of secondary thermal cycle, after primary thermal cycle 850 to 1350°C, on the amount of retained austenite, and however, there was a lesser effect of another factors, such as heating and cooling rates etc. on it. In the other hand, since the formation of globular austenite occured rapidly and abundantly during heating process in welding, as comparing the ordinary heat treatment, there was a variation in the amount of the retained austenite in very short time if holding at the peak temperature of tempering cycle. It was found that there was a fairly good correlation between the amount of retained austenite and toughness. When the grains, however, were remarkably coarsened by the primary thermal cycle similar to that near weld bond, the toughness was no longer improved regardless of the amount of retained austenite, unless the secondary thermal cycle being above 800°C. This secondary cycle resulted in the grain refinement and the formation of the enriched zone of alloying elements, where the stable austenite precipitated in 3rd thermal cycle, mainly, at prior austenite grain boundaries.

AB - The effect of retained austenite on notch toughness in HAZ of 9% nickel steel welds had been discussed in author's previous paper. In this paper, the above correlation and factors affecting on the formation of retained austenite during weld process were investigated in more detail by using the simulation technique. The obtained result indicated a noticeable effect of a peak temperature, in particular near 620°C being closer to ACCI temperature (about 630°C), of secondary thermal cycle, after primary thermal cycle 850 to 1350°C, on the amount of retained austenite, and however, there was a lesser effect of another factors, such as heating and cooling rates etc. on it. In the other hand, since the formation of globular austenite occured rapidly and abundantly during heating process in welding, as comparing the ordinary heat treatment, there was a variation in the amount of the retained austenite in very short time if holding at the peak temperature of tempering cycle. It was found that there was a fairly good correlation between the amount of retained austenite and toughness. When the grains, however, were remarkably coarsened by the primary thermal cycle similar to that near weld bond, the toughness was no longer improved regardless of the amount of retained austenite, unless the secondary thermal cycle being above 800°C. This secondary cycle resulted in the grain refinement and the formation of the enriched zone of alloying elements, where the stable austenite precipitated in 3rd thermal cycle, mainly, at prior austenite grain boundaries.

UR - http://www.scopus.com/inward/record.url?scp=85007717600&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85007717600&partnerID=8YFLogxK

U2 - 10.2207/qjjws1943.49.854

DO - 10.2207/qjjws1943.49.854

M3 - Article

AN - SCOPUS:85007717600

VL - 49

SP - 854

EP - 860

JO - Yosetsu Gakkai Shi/Journal of the Japan Welding Society

JF - Yosetsu Gakkai Shi/Journal of the Japan Welding Society

SN - 0021-4787

IS - 12

ER -