Effect of hydrogen on dislocation structure and strain-induced martensite transformation in 316L stainless steel

Abstract

Hydrogen forced that SIM distributed locally in a α′/γ laminated structure. Hydrogen changed dislocation structure from only cellular to planar dislocations. Hydrogen promoted strain-induced ordering and suppressed the formation of SIM.

Insight into hydrogen effect on a duplex medium-Mn steel revealed by in-situ nanoindentation test

“…The reduced martensite transformation with the presence of hydrogen can, in some way, be explained by the following mechanism: the reduced SFE will promote slip planarity and hinder dislocations crossslip, which unfavors the intersection of different slip systems that can locally increase the stress, and thus the nucleation of a 0 -martensite from those intersections are hindered. Hydrogen suppresses martensite transformation was reported in 316L stainless steel [52], where they observed a change of the dislocation structure from cellular to a mixture of cellular and planar mode. Although the reduction of martensite is expected to soften the material in the charged condition, it is not reflected on the current results.…”

“…Nonetheless, it is reasonable to imply that the strain induced martensite transformation is highly influenced by the addition of hydrogen through the alteration of SFE and phase stability. Since the nucleation sites of a 0 -martensite are proposed to be the intersections of different slip systems, as revealed via TEM and MFM [52,53]. The reduced martensite transformation with the presence of hydrogen can, in some way, be explained by the following mechanism: the reduced SFE will promote slip planarity and hinder dislocations crossslip, which unfavors the intersection of different slip systems that can locally increase the stress, and thus the nucleation of a 0 -martensite from those intersections are hindered.…”

Differentiating Diffuse Electron Scattering in Complex FCC Alloys via Fluctuation and Correlation Mapping

“…As a result, most studies have focused on single crystals where defects and other sources of diffuse scattering can be excluded, and interpretations of observed diffuse-scattering signals from real alloys remain inconclusive and speculative. For example, the origin of the diffuse-scattering signals at 1 3 {422} and 1 2 {311} positions, which are frequently found in FCC alloys, such as steels [26], Ni superalloys [12], and medium/high entropy alloys [7,13,[27][28][29][30][31][32][33][34],…”

Hydrogen on screw dislocation in Fe and W: Existence of 3D-compound and exotic segregation profile

“…Hydrogen segregation has often been studied at vacancy [14], surfaces [15,16], grain boundaries [2,14,[17][18][19][20][21][22][23], and dislocations [24][25][26][27][28][29][30]. For dislocations, hydrogen segregation was modeled either using elastic theory [31,32], Molecular Statics or Monte-Carlo (MC) simulations with semi-empirical potentials [31,[33][34][35], or using ab initio calculations to obtain energetic interactions used as input data in rigid-lattice MC simulations or mean-field (MF) models [25,29,30,36,37].…”