Use of inoculants to refine weld solidification structure and improve weldability in type 2090 AlLi alloy
15 Jan 2000-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing (Elsevier)-Vol. 276, Iss: 1, pp 48-57
TL;DR: In this article, grain refinement was induced in the weld fusion zones through inoculation with Ti, Ti+B and Zr, which reduced grain size considerably, with Zr being the most effective.
Abstract: The refinement of weld solidification structures will be useful not only because it is known to reduce the tendency to hot cracking, but also because the mechanical properties of the fusion zone are likely to be improved. In the current work, welds were produced in a type 2090 AlLi alloy using two filler materials based on types 2319 and 4043. Grain refinement was induced in the weld fusion zones through inoculation with Ti, Ti+B and Zr. Microstructural characterization showed that all three reduced grain size considerably, with Zr being the most effective. The structural refinement was found to reduce hot cracking susceptibility (measured by Varestraint testing), enhance post-weld age-hardening response and also improve tensile properties, especially ductility. The results showed that in the peak-aged condition the tensile elongations in the inoculated welds equalled or exceeded that in the base material.
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References
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TL;DR: In this paper, the weld beads obtained under (i) continuous current (CC), (ii) pulsed current (PC), and (iii) arc oscillation (AO) conditions for their macro- and microstructural details were compared.
Abstract: Clad 2 mm thick sheets of Russian 1441 grade Al-Li alloys were welded using a gas tungsten arc welding process (GTAW). Comparisons were made between the weld beads obtained under (i) continuous current (CC), (ii) pulsed current (PC), and (iii) arc oscillation (AO) conditions for their macro- and microstructural details. In the case of CC GTAW, sound welds could be produced only under a narrow range of welding parameters. Centre line cracks, which occurred in CC GTAW welds under certain conditions, were halted by switching to PC or AO conditions while the welding was in progress. Microstructural refinement was significant in the case of PC and AO GTA welding.
105 citations
TL;DR: In this article, the effects of various additions to binary Al-3Li on electron-beam weld solidification structures and tensile properties were examined, including Zr for grain refinement, Mg for solid solution strengthening, Cu for precipitation strengthening, and Co for dispersion strengthening.
16 citations