Enhanced plasticity in Zr-based bulk metallic glasses by hydrogen

Effectiveness of hydrogen microalloying in bulk metallic glass design

“…Both modifications are also found to be amorphous in this case, because their respective XRD patterns only feature halos characteristic of the glassy state. The halo of Ar-cast Zr64, however, appears sharper than that of the hydrogen-processed counterpart, which is in line with the finding that hydrogen microalloying generates enhanced GFA [15][16][17]. temperature aging.…”

“…Recently, minor doping with hydrogen has been found to simultaneously improve the glass-forming ability (GFA) and the compressive ductility of Zr-based BMGs [15][16][17]. Such processing-induced microalloying incorporates hydrogen directly into the glassy structure, resulting in a higher packing density, as illustrated by positron annihilation spectroscopy (PAS) [15], and increased local inhomogeneity [16].…”

Stress-Corrosion Interactions in Zr-Based Bulk Metallic Glasses

“…Most work related to environmentally induced cracking of Zr-based BMGs was done on hydrogen effects (e.g., [44][45][46][47][48][49][50][51][52]) and on corrosion fatigue [53][54][55][56][57][58][59][60]. Studies on stress corrosion cracking of Zr-based BMGs are rather scarce [9,10,13,53,61].…”

Response of large-deformation behavior to strain rates in a bulk-metallic glass by hydrogen

“…Bulk-metallic glasses (BMG), have aroused wide concerns for their potential application value as engineering structural materials due to their excellent mechanical, physical and chemical properties [1,2]: high strength; high hardness; high strength to weight ratio; superior elastic limit; low coefficient of friction; high scratch and wear resistance; good corrosion resistance; net-shape castability; high luster surfaces and good soft magnetic behavior, etc. However, the plastic deformation of BMGs at room temperature is highly localized in the very narrow shear bands and the volume fraction of the shear bands among the total volume of the entire alloy is relatively low, resulting in the brittleness of a majority of BMGs [3,4]. A large number of studies show that the BMGs usually fracture after experiencing plastic strain less than 2% under compression, while their elongation closes to zero during tensile tests [5].…”

“…Very recently, it's reported that hydrogen addition can increase the glass plasticity significantly, which is attributed to the large amount of free volume induced by hydrogen addition [4,6]. The free volume resulting from the less densely packed structure in metallic glasses provides additional sites for hydrogen occupation when compared to that of the corresponding crystalline materials [7].…”