Dissimilar Laser Welding of Ti-6Al-4V to Ti-6Al-6V-2Sn

Abstract:

Notched tensile strength (NTS) of the Ti-6Al-4V (Ti-6-4) to Ti-6A16V-2Sn (Ti-6-6-2) dissimilar laser welds were determined, which had been subjected to post-weld heat treatment (PWHT) over the temperature range of 482-704°C. The results indicated for the weld with the PWHT at 482°C the fusion zone (FZ) and heat-affected zone (HAZ) showed a peak hardness, as compared with other welds at the counterpart regions, whereas, the weld with the PWHT at 704°C had the lowest hardness among the welds. In all the welds, the FZ of the weld subjected to PWHT at 482°C possessed the lowest NTS, while the as-welded and the weld with PWHT at 704°C had superior NTS to others. The presence of grain boundary α, which promoted grain boundary shear, accounted for the typical features of mainly transgranular fracture with intergranular dimples of the welds.

• Periodical: Advanced Materials Research (Volumes 295-297)
• Pages: 2353-2357
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.295-297.2353
• Online since: July 2011
• Authors: C. Y. Chiu, M.Y. Lu, L.W. Tsay
• Keywords: Laser Welding, Notched Tensile Strength, Ti-6A16v-2Sn, Ti6Al4V

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[12] L. W. Tsay, C. X. Lee and C. Chen, Mat. Trans, 50(2009), 1785-1791. 3 Figure 1 Schematic diagram showing the dimendions of double-edge notched tensile specimen. Figure 2 Shows the variation of microhardness from the centerline of the FZ to the unaffected base metal (BM) in various welds with the PWHT over the temperature range of 482-704°C. Figure 4 The NTS values of the welds in different conditions. Figure 3 The FZ hardness of distinct titanium welds in the as-welded and PWHT conditions. a 1um 10um a Figure 5 The SEM micrographs showing the microstructures of various specimens; (a)the BM of Ti-6Al-4V; (b) the BM of Ti-6Al-6V-2Sn; (c)the as-welded FZ; (d) the FZ with the PWHT at 704℃. Figure 6 SEM fractographs of the (a) as-received Ti-6Al-4V; (b) the FZ in the AW condition; (c) the FZ with a PWHT at 482oC c 10um b 10um d 1um c 1um 1um b

DOI: 10.2320/matertrans.m2009001