Nanosecond pulsed laser irradiation induced hierarchical micro/nanostructures on Zr-based metallic glass substrate

Abstract

• Hierarchical micro/nanostructures were fabricated on a metallic glass substrate by nanosecond pulsed laser irradiation.• It retained amorphous characteristic and exhibited uniform element distribution.• Irradiation parameters induced change from cotton-like to particle-like nanostructure.• Formation mechanism and mechanical properties were investigated. A large effective surface area is beneficial to enhance the applications of metallic glasses (MGs) in heterogeneous catalysis and biomedical engineering. For the purpose of increasing effective surface area, in this study, hierarchical micro/nanostructures were fabricated on a Zr-based MG substrate by nanosecond pulsed laser irradiation. Experimental results indicated that a layer of micron-scale laser pulse tracks covered by a cotton-like MG thin film with nanometer-scale microstructure was formed in the laser irradiated region. This hierarchical micro/nanostructures retained amorphous characteristic and exhibited uniform element distribution. Its formation mechanism was investigated by analyzing the laser irradiation process and morphologies. Nanoindentation results indicated that the cotton-like MG thin film was very loose and soft compared to the as-cast MG substrate, showing different plastic deformation behavior. Results from this study indicate that nanosecond pulsed laser irradiation is an effective method to generate hierarchical micro/nanostructures on MG substrates, which can increase their effective surface areas and improve their potential applications as biomaterials and catalysts.

Optimizing the antimicrobial performance of metallic glass composites through surface texturing

“…These microgrooves and protrusions are formed after laser texturing as a result of the applied laser fluence distribution and the subsequent vaporization of the processed material. However, the relatively high laser power used has led to a non-uniform wrinkled surface similar to that already reported in the literature [29,30]. An increase of laser fluence to 1.39 J/cm 2 caused a rise in average roughness, 1.70 ± 0.48 μm, but the obtained texture is more irregular with broader (up to 60 μm) grooves and triangle shaped islands.…”

Surface Modification of the Bulk Metallic Glass Zr$_{46}$Cu$_{36.8}$Ag$_{9.2}$Al$_8$ Triggered by Millisecond Laser Irradiation

“…The decrease in activation energy was previously observed for copper oxide due Formation of nanocrystals is one of the methods to prevent transmission of shear band [46,27,7,47,48,49,50]. Detection of the crystallines in this work is one of the aspects indicating potential for industrial applications.…”

THE STUDY OF INFLUENCE OF MILLISECOND LASER IRRADIATION ON THE MORPHOLOGY AND CRYSTALLIZATION OF A THERMO-ACTIVATION ZONE FOR Zr-Cu-Ag-Al BULK AMORPHOUS ALLOY

“…При этом весь образец остался в аморфном состоянии. В работе [7] на поверхности АМС получена композитная структура, представляющая собой аморфную матрицу с вкраплениями микро-и нано-частиц B 2 -фазы (CuZr), в работе [8] удалось получить кристаллические структуры на поверхности образца путем осаждения абляционных частиц. Известно, что при комнатной температуре пластическая деформация металлических стекол происходит за счет образования полос скольжения, в отличие от кристаллических сплавов, у которых деформация осуществляется за счет движения и размножения дислокаций.…”