Abstract
Precision welded joints, produced between fused silica glass and aluminium by a newly-developed picosecond-pulse laser technique, have been analysed for the first time using a full range of electron microscopy methods. The welds were produced as lap joints by focusing a 1.2 μm diameter laser beam through the transparent glass top sheet, slightly below the surface of the metal bottom sheet. Despite the extremely short interaction time, extensive reaction was observed in the weld zone, which involved the formation of nanocrystalline silicon and at least two transitional alumina phases, γ- and δ-Al2O3. The weld formation process was found to be complex and involved: the formation of a constrained plasma cavity at the joint interface, non-linear absorption in the glass, and the creation of multiple secondary keyholes in the metal substrate by beam scattering. The joint area was found to expand outside of the main interaction volume, as the energy absorbed into the low conductivity and higher melting point silica glass sheet melted the aluminium surface across a wider contact area. The reasons for the appearance of nanocrystalline Si and transitional alumina reaction products within the welds are discussed.
Original language | English |
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Pages (from-to) | 53-62 |
Number of pages | 10 |
Journal | Materials Characterization |
Volume | 120 |
Early online date | 16 Aug 2016 |
DOIs | |
Publication status | Published - Oct 2016 |
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Dive into the research topics of 'Characterisation of weld zone reactions in dissimilar glass-to-aluminium pulsed picosecond laser welds'. Together they form a unique fingerprint.Profiles
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Richard Carter
- School of Engineering & Physical Sciences - Associate Professor
- School of Engineering & Physical Sciences, Institute of Photonics and Quantum Sciences - Associate Professor
Person: Academic (Research & Teaching)