scholarly journals Effect of strain rate on hydrogen embrittlement susceptibility of twinning-induced plasticity steel pre-charged with high-pressure hydrogen gas

2016 ◽  
Vol 41 (34) ◽  
pp. 15362-15372 ◽  
Author(s):  
B. Bal ◽  
M. Koyama ◽  
G. Gerstein ◽  
H.J. Maier ◽  
K. Tsuzaki
Author(s):  
Daichi Tsurumi ◽  
Hiroyuki Saito ◽  
Hirokazu Tsuji

As an alternative method to slow strain rate technique (SSRT) under high-pressure hydrogen gas evaluation, SSRT was performed with a cathodically charged specimen. Cr-Mo low alloy steel with a tensile strength of 1000 MPa grade was selected as a test material. Cathodic charging was performed in 3% NaCl solution and at a current density in the range of 50–600 A/m2. The effect of specimen size on the hydrogen embrittlement properties was evaluated. Relative reduction of area (RRA) values obtained by tests at a cathode current density of 400 A/m2 were equivalent to those performed in hydrogen gas at pressures of 10 to 35 MPa. Fracture surface observations were also performed using scanning electron microscopy (SEM). The quasi-cleavage fracture surface was observed only after rupture of small specimens that were subjected to hydrogen charged tests. It was also necessary for the diameter of the specimen to be small to form the quasi-cleavage fracture surface. The results indicated that to simulate the high-pressure hydrogen gas test, a specimen with a smaller parallel section diameter that is continuously charged until rupture is preferable.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Fan Bao ◽  
Kaiyu Zhang ◽  
Zhengrong Zhou ◽  
Wenli Zhang ◽  
Xiao Cai ◽  
...  

Purpose The purpose of this paper is to demonstrate the effect of δ-ferrite on the susceptibility to hydrogen embrittlement of type 304 stainless steel in hydrogen gas environment. Design/methodology/approach The mechanical properties of as-received and solution-treated specimens were investigated by the test of tensile and fatigue crack growth (FCG) in 5 MPa argon and hydrogen. Findings The presence of δ-ferrite reduced the relative elongation and the relative reduction area (H2/Ar) of 304 stainless steel, indicating that δ-ferrite increased the susceptibility of hydrogen embrittlement in 304 stainless steel. Moreover, δ-ferrite promoted the fatigue crack initiation and propagation at the interface between δ-ferrite and austenite. The FCG tests were used to investigate the effect of δ-ferrite on the FCG rate in hydrogen gas environment, and it was found that δ-ferrite accelerated the FCG rate, which was attributed to rapid diffusion and accumulation of hydrogen around the fatigue crack tip through δ-ferrite in high-pressure hydrogen gas environment. Originality/value The dependence of the susceptibility to hydrogen embrittlement on δ-ferrite was first investigated in type 304 steel in hydrogen environment with high pressures, which provided the basis for the design and development of a high strength, hydrogen embrittle-resistant austenitic stainless steel.


2016 ◽  
Vol 258 ◽  
pp. 259-264
Author(s):  
Saburo Matsuoka ◽  
Junichiro Yamabe ◽  
Hisao Matsunaga

For slow strain rate tensile (SSRT) test in hydrogen gas, the degradation in relative reduction in area (RRA) of 300-series austenitic stainless steels is mainly attributed to hydrogen-assisted surface crack growth (HASCG) accompanied by quasi-cleavages. To establish novel criteria for authorizing various austenitic stainless steels for use in high-pressure gaseous hydrogen, a mechanism of the HASCG should be elucidated. At first, this study performed SSRT tests on six types of austenitic stainless steels, Types 304, 316, 316L, 306(hi-Ni), 304N2 and 304(N), in high-pressure hydrogen gas and showed that the RRAs were successfully quantified in terms of a newly-proposed nickel-equivalent equation. Then, to elucidate the microscopic mechanism of the HASCG, elasto-plastic fracture toughness (JIC), fatigue crack growth (FCG) and fatigue life tests on Types 304, 316 and 316L were carried out in high-pressure hydrogen gas. The results demonstrated that the SSRT surface crack grew via the same mechanism as for the JIC and fatigue cracks, i.e., these cracks successively grow with a sharp shape under the loading process, due to local slip deformations near the crack tip by hydrogen. Detailed observations of SSRT surface cracks on Types 304 and 316L were also performed, exhibiting that the onset of the HASCG occurred at the true strain of 0.1 or larger in high-pressure hydrogen gas.


2014 ◽  
Vol 63 (10) ◽  
pp. 523-527 ◽  
Author(s):  
Kenichi Koide ◽  
Takao Minami ◽  
Toshirou Anraku ◽  
Akihiro Iwase ◽  
Hiroyuki Inoue

Author(s):  
Hideki Nakagawa

Practical application of fuel cell vehicle has started in the world, and high-pressure hydrogen tanks are currently considered to be the mainstream hydrogen storage system for commercially implemented fuel cell vehicle. Application of metallic materials to the components of high-pressure hydrogen storage system: hydrogen tanks, valves, measuring instructions and so on, have been discussed. In this work, tensile properties of four types of stainless steels were evaluated in 45MPa (6527psig) and 75MPa (10878psig) high-pressure gaseous hydrogen at a slow strain rate of 3×10−6 s−1 at ambient temperature. Type 316L (UNS S31603) stainless steel hardly showed ductility loss in gaseous hydrogen, since it had stable austenitic structure. On the other hand, Type 304 (UNS S30400) metastable austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of strain induced martensitic phase. Likewise, Type 205 (UNS S20500) nitrogen-strengthened austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, though it had stable austenitic structure in the same manner as Type 316L. The ductility loss of Type 205 was due to the hydrogen embrittlement of austenitic phase resulting from the formation of planar dislocation array. Furthermore, Type 329J4L (UNS S31260) duplex stainless steel showed extreme ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of ferritic phase.


Hyomen Kagaku ◽  
2015 ◽  
Vol 36 (11) ◽  
pp. 562-567
Author(s):  
Hisao MATSUNAGA ◽  
Junichiro YAMABE ◽  
Saburo MATSUOKA

Author(s):  
Z. Y. Li ◽  
C. L. Zhou ◽  
Y. Z. Zhao ◽  
Z. L. Hua ◽  
L. Zhang ◽  
...  

Crack growth analysis (CGA) was applied to estimate the cycle life of the high-pressure hydrogen equipment constructed by the practical materials of 4340 (two heats), 4137, 4130X, A286, type 316 (solution-annealed (SA) and cold-worked (CW)), and type 304 (SA and CW) in 45, 85 and 105 MPa hydrogen and air. The wall thickness was calculated following five regulations of the High Pressure Gas Safety Institute of Japan (KHK) designated equipment rule, KHKS 0220, TSG R0002, JB4732, and ASME Sec. VIII, Div. 3. We also applied CGA for four typical model materials to discuss the effect of ultimate tensile strength (UTS), pressure and hydrogen sensitivity on the cycle life of the high-pressure hydrogen equipment. Leak before burst (LBB) was confirmed in all practical materials in hydrogen and air. The minimum KIC required for LBB of the model material with UTS of even 1500 MPa was 170 MPa·m0.5 in 105 MPa. Cycle life qualified 103 cycles for all practical materials in air. In 105 MPa hydrogen, the cycle life by KIH was much shorter than that in air for two heats of 4340 and 4137 sensitive to hydrogen gas embrittlement (HGE). The cycle life of type 304 (SA) sensitive to HGE was almost above 104 cycles in hydrogen, while the cycle life of type 316 (SA and CW) was not affected by hydrogen and that of A286 in hydrogen was near to that in air. It was discussed that the cycle life increased with decreasing pressure or UTS in hydrogen. This behavior was due to that KIH increased or fatigue crack growth (FCG) decreased with decreasing pressure or UTS. The cycle life data of the model materials under the conditions of the pressure, UTS, KIH, FCG and regulations in both hydrogen and air were proposed quantitatively for materials selection for high-pressure hydrogen storage.


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