Microstructural characterization and formation of alpha ' martensite phase in Ti-6Al-4V alloy butt joints produced by friction stir and gas tungsten arc welding processes
Artikel i vetenskaplig tidskrift, 2013

The obtained microstructures of a Ti-6Al-4V alloy welded by Gas Tungsten Arc Welding (GTAW) and Friction Stir Welding (FSW) were investigated and evaluated quantitatively. In the GTAW method, the effect of current was examined so that the samples were subjected to various currents between 90 and 120 A. In the FSW process, samples were welded by different rotational speeds (450-850 rpm). Non-destructive tests including Visual and Radiography Tests (VT and RT) were used to identify defect-free samples. The microstructural studies by electron microscopes revealed formation of different phases in the weld area of the samples welded via mentioned methods. The recorded peak temperatures in the weld regions compared favorably with the expectations about the evolved microstructures. A bimodal microstructure was just obtained in the FSWed sample with a peak temperature below beta transus temperature (T < 995 degrees C). alpha' martensite phase, which is an acicular and strengthening phase in this alloy, was only observed in FSWed specimens.

Friction stir welding

Gas tungsten arc welding

alpha ' Martensite phase

Titanium alloys

Författare

Mohsen Esmaily

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Nooshin Mortazavi Seyedeh

Chalmers, Material- och tillverkningsteknik, Yt- och mikrostrukturteknik

P. Todehfalah

University of Manchester

Masoud Rashidi

Kungliga Tekniska Högskolan (KTH)

Materials & Design

1873-4197 (eISSN)

Vol. 47 143-150

Ämneskategorier

Materialteknik

DOI

10.1016/j.matdes.2012.12.024

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Senast uppdaterat

2018-02-28