Electron backscatter diffraction characterization of fatigue crack growth in laser metal wire deposited Ti-6Al-4V
Artikel i vetenskaplig tidskrift, 2018

By additive manufacturing (AM) there is a feasibility of producing near net shape components in basically one step from 3D CAD model to final product. The interest for AM is high and during the past decade a lot of research has been carried out in order to understand the influence from process parameters on the microstructure and furthermore on the mechanical properties. In the present study laser metal wire deposition of Ti-6Al-4V has been studied in detail with regard to its fatigue crack propagation characteristics. Two specimen orientations, parallel and perpendicular to the deposition direction, have been evaluated at room temperature and at 250 °C. No difference in the fatigue crack growth rate could be confirmed for the two specimen orientations. However, in the fractographic study it was observed that the tortuosity varied between certain regions on the fracture surface. The local crack path characteristic could be related to the alpha colony size and/or the crystallographic orientation. Moreover, large areas exhibiting similar crystallographic orientation were observed along the prior beta grain boundaries, which were attributed to the wide alpha colonies frequently observed along the prior beta grain boundaries.

Författare

Pia Åkerfeldt

Luleå tekniska universitet

Magnus Hörnqvist Colliander

Chalmers, Fysik, Materialens mikrostruktur

Robert Pederson

Högskolan Väst

Luleå tekniska universitet

Marta-Lena Antti

Luleå tekniska universitet

Materials Characterization

1044-5803 (ISSN)

Vol. 135 245-256

Ämneskategorier

Materialteknik

Annan materialteknik

Metallurgi och metalliska material

Styrkeområden

Materialvetenskap

DOI

10.1016/j.matchar.2017.11.041

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Senast uppdaterat

2021-10-22