Abstract
The role of the dynamic interactions between hydrogen and the strain-induced martensite transformation in the hydrogen embrittlement of type 304 stainless steel has been investigated by fractographic observations after a modified hydrogen charging. The modified charging is cathodically conducted in 3.5% NaCl solution at 80°C under aerated conditions while preventing the dissolution of chlorine and oxygen gases evolving on the platinum counter electrode, thus increasing the amount of hydrogen thermally desorbed at low temperatures. Upon tensile testing at 160°C, plastic deformation of the austenite phase in the stainless steel occurs, but no strain-induced martensite transformation occurs. The fracture surface of the hydrogen-charged specimen exhibits the double-cup mode and consists of microscopic shallow dimples. Upon tensile testing at 25°C, the martensite transformation and plastic deformation both occur and are intricately related; a brittle area is observed on the outer part of the fracture surface that exhibits both transgranular and intergranular fracture. At-196°C, the martensite transformation increases, but the amount of plastic deformation decreases and the amount of intergranular fracture increases. It is found that, when the martensite transformation occurs before hydrogen charging, the amount of intergranular fracture decreases. Moreover, when charged hydrogen is trapped in defects in the austenite phase, the amount of intergranular fracture also decreases. The present study indicates that the dynamic interactions between hydrogen and the martensite transformation play an important role in the hydrogen embrittlement of type 304 stainless steel.
| Original language | English |
|---|---|
| Pages (from-to) | 1772-1780 |
| Number of pages | 9 |
| Journal | ISIJ International |
| Volume | 55 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - 2015 |
Fingerprint
Keywords
- Fractography
- Hydrogen embrittlement
- Martensite
- Stainless steel
ASJC Scopus subject areas
- Mechanical Engineering
- Mechanics of Materials
- Materials Chemistry
- Metals and Alloys
Cite this
Role of dynamic interactions between hydrogen and straininduced martensite transformation in hydrogen embrittlement of type 304 stainless steel. / Yoshioka, Yuma; Yokoyama, Ken'ichi; Sakai, Jun'ichi.
In: ISIJ International, Vol. 55, No. 8, 2015, p. 1772-1780.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Role of dynamic interactions between hydrogen and straininduced martensite transformation in hydrogen embrittlement of type 304 stainless steel
AU - Yoshioka, Yuma
AU - Yokoyama, Ken'ichi
AU - Sakai, Jun'ichi
PY - 2015
Y1 - 2015
N2 - The role of the dynamic interactions between hydrogen and the strain-induced martensite transformation in the hydrogen embrittlement of type 304 stainless steel has been investigated by fractographic observations after a modified hydrogen charging. The modified charging is cathodically conducted in 3.5% NaCl solution at 80°C under aerated conditions while preventing the dissolution of chlorine and oxygen gases evolving on the platinum counter electrode, thus increasing the amount of hydrogen thermally desorbed at low temperatures. Upon tensile testing at 160°C, plastic deformation of the austenite phase in the stainless steel occurs, but no strain-induced martensite transformation occurs. The fracture surface of the hydrogen-charged specimen exhibits the double-cup mode and consists of microscopic shallow dimples. Upon tensile testing at 25°C, the martensite transformation and plastic deformation both occur and are intricately related; a brittle area is observed on the outer part of the fracture surface that exhibits both transgranular and intergranular fracture. At-196°C, the martensite transformation increases, but the amount of plastic deformation decreases and the amount of intergranular fracture increases. It is found that, when the martensite transformation occurs before hydrogen charging, the amount of intergranular fracture decreases. Moreover, when charged hydrogen is trapped in defects in the austenite phase, the amount of intergranular fracture also decreases. The present study indicates that the dynamic interactions between hydrogen and the martensite transformation play an important role in the hydrogen embrittlement of type 304 stainless steel.
AB - The role of the dynamic interactions between hydrogen and the strain-induced martensite transformation in the hydrogen embrittlement of type 304 stainless steel has been investigated by fractographic observations after a modified hydrogen charging. The modified charging is cathodically conducted in 3.5% NaCl solution at 80°C under aerated conditions while preventing the dissolution of chlorine and oxygen gases evolving on the platinum counter electrode, thus increasing the amount of hydrogen thermally desorbed at low temperatures. Upon tensile testing at 160°C, plastic deformation of the austenite phase in the stainless steel occurs, but no strain-induced martensite transformation occurs. The fracture surface of the hydrogen-charged specimen exhibits the double-cup mode and consists of microscopic shallow dimples. Upon tensile testing at 25°C, the martensite transformation and plastic deformation both occur and are intricately related; a brittle area is observed on the outer part of the fracture surface that exhibits both transgranular and intergranular fracture. At-196°C, the martensite transformation increases, but the amount of plastic deformation decreases and the amount of intergranular fracture increases. It is found that, when the martensite transformation occurs before hydrogen charging, the amount of intergranular fracture decreases. Moreover, when charged hydrogen is trapped in defects in the austenite phase, the amount of intergranular fracture also decreases. The present study indicates that the dynamic interactions between hydrogen and the martensite transformation play an important role in the hydrogen embrittlement of type 304 stainless steel.
KW - Fractography
KW - Hydrogen embrittlement
KW - Martensite
KW - Stainless steel
UR - http://www.scopus.com/inward/record.url?scp=84941134193&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84941134193&partnerID=8YFLogxK
U2 - 10.2355/isijinternational.ISIJINT-2015-132
DO - 10.2355/isijinternational.ISIJINT-2015-132
M3 - Article
AN - SCOPUS:84941134193
VL - 55
SP - 1772
EP - 1780
JO - ISIJ International
JF - ISIJ International
SN - 0915-1559
IS - 8
ER -