Constitutive modelling and identification of parameters of the plastic strain-induced martensitic transformation in 316L stainless steel at cryogenic temperatures

Low cycle fatigue (LCF) tests were carried out in a wide temperature range (20°C-650°C)at strain rates of 1×10-4/s-1×10-2/s for 17% cold worked (CW) 316L stainless steel to investigate the conditions for the occurrence of dynamic strain aging (DSA) and its effects on material properties during LCF deformation. DSA introduced anomalous changes of LCF properties, and the DSA regime under LCF loading condition coincided with that in tensile loading condition. During LCF deformation, dynamic stain aging can be manifested in the forms of the occurrence of the plateau or the peak in the variation of cyclic peak stress with temperature, the negative temperature dependence of plastic strain amplitude or softening ratio, the negative strain rate sensitivity, and the negative strain rate dependence of plastic strain amplitude or softening ratio.

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Charpy Impact Properties of Hydrogen-Exposed 316L Stainless Steel at Ambient and Cryogenic Temperatures

Metals ◽

10.3390/met9060625 ◽

2019 ◽

Vol 9 (6) ◽

pp. 625 ◽

Cited By ~ 5

Author(s):

Le Thanh Hung Nguyen ◽

Jae-Sik Hwang ◽

Myung-Sung Kim ◽

Jeong-Hyeon Kim ◽

Seul-Kee Kim ◽

...

Keyword(s):

Fracture Toughness ◽

Stainless Steel ◽

Low Temperatures ◽

316L Stainless Steel ◽

Charpy Impact ◽

Cryogenic Temperatures ◽

Absorbed Energy ◽

Impact Properties ◽

Charging Time ◽

The Impact

316L stainless steel is a promising material candidate for a hydrogen containment system. However, when in contact with hydrogen, the material could be degraded by hydrogen embrittlement (HE). Moreover, the mechanism and the effect of HE on 316L stainless steel have not been clearly studied. This study investigated the effect of hydrogen exposure on the impact toughness of 316L stainless steel to understand the relation between hydrogen charging time and fracture toughness at ambient and cryogenic temperatures. In this study, 316L stainless steel specimens were exposed to hydrogen in different durations. Charpy V-notch (CVN) impact tests were conducted at ambient and low temperatures to study the effect of HE on the impact properties and fracture toughness of 316L stainless steel under the tested temperatures. Hydrogen analysis and scanning electron microscopy (SEM) were conducted to find the effect of charging time on the hydrogen concentration and surface morphology, respectively. The result indicated that exposure to hydrogen decreased the absorbed energy and ductility of 316L stainless steel at all tested temperatures but not much difference was found among the pre-charging times. Another academic insight is that low temperatures diminished the absorbed energy by lowering the ductility of 316L stainless steel.

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Influence of the Martensitic Transformation on the Microscale Plastic Strain Heterogeneities in a Duplex Stainless Steel

Metallurgical and Materials Transactions A ◽

10.1007/s11661-016-3858-z ◽

2016 ◽

Vol 48 (1) ◽

pp. 20-25 ◽

Cited By ~ 5

Author(s):

Audrey Lechartier ◽

Guilhem Martin ◽

Solène Comby ◽

Francine Roussel-Dherbey ◽

Alexis Deschamps ◽

...

Keyword(s):

Stainless Steel ◽

Martensitic Transformation ◽

Plastic Strain ◽

Duplex Stainless Steel

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Cyclic Stress-Strain Response and Martensitic Transformation Behavior for Type 304 Stainless Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.510.114 ◽

2014 ◽

Vol 510 ◽

pp. 114-117 ◽

Cited By ~ 6

Author(s):

Hiroshi Hamasaki ◽

Eiichiro Ishimaru ◽

Fusahito Yoshida

Keyword(s):

Stainless Steel ◽

Martensitic Transformation ◽

Plastic Strain ◽

Volume Fraction ◽

Early Stage ◽

Large Strain ◽

Strain Curve ◽

304 Stainless Steel ◽

Stress Strain ◽

Martensite Volume Fraction

Stress-strain responses of type SUS304 stainless steel at large strain under uniaxial tension and cyclic loading were investigated with special reference to plastic strain induced martensitic transformation. From the experiment it was found that the martensitic transformation plays an important role for the workhardening of the material at large strain, and a new finding from the cyclic experiment is that the stagnation of martensitic transformation appears at an early stage of reverse deformation. The evolutions of martensite volume fraction during monotonic and cyclic deformations were calculated by Stringfellow model, and it was found that the model is accurate enough for predicting the martensite volume fraction vs. plastic strain curve under monotonic loading case. On the other hand, it significantly overestimates the evolution of martensite volume fraction in a cyclic deformation.

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