The effects of austenitizing time on bainite continuous transformation kinetics of AISI 4340 steel

Hong Zhuang Zhao, Seok Jae Lee, Young Kook Lee, Xiang Hua Liu, Guo Dong Wang

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The effects of austenitizing time on bainite continuous transformation kinetics are investigated for AISI 4340 steel in dilatometric experiments. Dilatometric specimens were heated up to 950°C, and austenitized for 10-120 minutes, followed by rapid cooling to 550°C in 20 s, and in the following 120 minutes cooled to 350°C, and then quenched to room temperature at l00°C/s. The bainite transformation start temperature (Bs) and 50% transformation temperature (Bm) vary obviously with holding time. The bainite transformation finish temperature (Bf) remains almost the same. The reason of Bs raises with the holding time may be due to the precipitation of AlN and TiC or other carbide or nitride particles on prior austenite grain boundaries. In fact the trends that the bainitic transformation rate varied with its volume fraction ξ can be separated into three stages: I. rapid increase stage; II. slowly decrease stage; III. rapid decrease stage. The reasons for the above phenomenon may be due to the effects of the decreasing of temperature, the diffusion of carbon during the continuous transformation process, and effects of the alloy composition, etc.

Original languageEnglish
Pages (from-to)53-56
Number of pages4
JournalCailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment
Volume27
Issue number4
Publication statusPublished - 2006 Aug 1

Fingerprint

bainite
Bainite
Steel
steels
Kinetics
kinetics
Temperature
Bainitic transformations
temperature
Nitrides
Austenite
Carbides
austenite
Volume fraction
Grain boundaries
carbides
Carbon
nitrides
Cooling
grain boundaries

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Physics and Astronomy(all)

Cite this

@article{4f07866b44d947839f3d50c2cc469f61,
title = "The effects of austenitizing time on bainite continuous transformation kinetics of AISI 4340 steel",
abstract = "The effects of austenitizing time on bainite continuous transformation kinetics are investigated for AISI 4340 steel in dilatometric experiments. Dilatometric specimens were heated up to 950°C, and austenitized for 10-120 minutes, followed by rapid cooling to 550°C in 20 s, and in the following 120 minutes cooled to 350°C, and then quenched to room temperature at l00°C/s. The bainite transformation start temperature (Bs) and 50{\%} transformation temperature (Bm) vary obviously with holding time. The bainite transformation finish temperature (Bf) remains almost the same. The reason of Bs raises with the holding time may be due to the precipitation of AlN and TiC or other carbide or nitride particles on prior austenite grain boundaries. In fact the trends that the bainitic transformation rate varied with its volume fraction ξ can be separated into three stages: I. rapid increase stage; II. slowly decrease stage; III. rapid decrease stage. The reasons for the above phenomenon may be due to the effects of the decreasing of temperature, the diffusion of carbon during the continuous transformation process, and effects of the alloy composition, etc.",
author = "Zhao, {Hong Zhuang} and Lee, {Seok Jae} and Lee, {Young Kook} and Liu, {Xiang Hua} and Wang, {Guo Dong}",
year = "2006",
month = "8",
day = "1",
language = "English",
volume = "27",
pages = "53--56",
journal = "Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment",
issn = "1009-6264",
publisher = "Editorial Office of Transactions of Materials and Heat Treatment",
number = "4",

}

The effects of austenitizing time on bainite continuous transformation kinetics of AISI 4340 steel. / Zhao, Hong Zhuang; Lee, Seok Jae; Lee, Young Kook; Liu, Xiang Hua; Wang, Guo Dong.

In: Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment, Vol. 27, No. 4, 01.08.2006, p. 53-56.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The effects of austenitizing time on bainite continuous transformation kinetics of AISI 4340 steel

AU - Zhao, Hong Zhuang

AU - Lee, Seok Jae

AU - Lee, Young Kook

AU - Liu, Xiang Hua

AU - Wang, Guo Dong

PY - 2006/8/1

Y1 - 2006/8/1

N2 - The effects of austenitizing time on bainite continuous transformation kinetics are investigated for AISI 4340 steel in dilatometric experiments. Dilatometric specimens were heated up to 950°C, and austenitized for 10-120 minutes, followed by rapid cooling to 550°C in 20 s, and in the following 120 minutes cooled to 350°C, and then quenched to room temperature at l00°C/s. The bainite transformation start temperature (Bs) and 50% transformation temperature (Bm) vary obviously with holding time. The bainite transformation finish temperature (Bf) remains almost the same. The reason of Bs raises with the holding time may be due to the precipitation of AlN and TiC or other carbide or nitride particles on prior austenite grain boundaries. In fact the trends that the bainitic transformation rate varied with its volume fraction ξ can be separated into three stages: I. rapid increase stage; II. slowly decrease stage; III. rapid decrease stage. The reasons for the above phenomenon may be due to the effects of the decreasing of temperature, the diffusion of carbon during the continuous transformation process, and effects of the alloy composition, etc.

AB - The effects of austenitizing time on bainite continuous transformation kinetics are investigated for AISI 4340 steel in dilatometric experiments. Dilatometric specimens were heated up to 950°C, and austenitized for 10-120 minutes, followed by rapid cooling to 550°C in 20 s, and in the following 120 minutes cooled to 350°C, and then quenched to room temperature at l00°C/s. The bainite transformation start temperature (Bs) and 50% transformation temperature (Bm) vary obviously with holding time. The bainite transformation finish temperature (Bf) remains almost the same. The reason of Bs raises with the holding time may be due to the precipitation of AlN and TiC or other carbide or nitride particles on prior austenite grain boundaries. In fact the trends that the bainitic transformation rate varied with its volume fraction ξ can be separated into three stages: I. rapid increase stage; II. slowly decrease stage; III. rapid decrease stage. The reasons for the above phenomenon may be due to the effects of the decreasing of temperature, the diffusion of carbon during the continuous transformation process, and effects of the alloy composition, etc.

UR - http://www.scopus.com/inward/record.url?scp=33750417521&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750417521&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:33750417521

VL - 27

SP - 53

EP - 56

JO - Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment

JF - Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment

SN - 1009-6264

IS - 4

ER -