The effect of manufacturing defects on the high-cycle fatigue of electron-beam-welded Ti-6Al-4V titanium alloy: experimental and numerical analysis

Abstract

Purpose

Electron-beam welding has been widely used in industry to join different titanium alloys (Ti-6Al-4V) components. During welding production defects, such as porosity, lack of penetration or thinning are often observed. High-cycle fatigue (HCF) tests have been performed on welded specimens to understand the effect of weld defects on fatigue capabilities. The fatigue life of different types of “defective” welds has been compared against a non-welded reference specimen.

Design/methodology/approach

The results of the experimental campaign have been correlated with finite elements models.

Findings

It is concluded the geometry produced by the weld process, e.g. toe radius and under-bead shape, and the related stress raisers play a relevant role on fatigue capabilities of welds. This conclusion is valid only for a Ti-6Al-4V T-joint weld and only for flaw initiation. Knock down in materials properties has not been considered.

Originality/value

There is a lack of HCF fatigue data for welds of this geometry and material in the open literature. The paper is of relevance for industrial application and practical interest, although a lot more validation tests are required to draw a final conclusion.

Citation

Rubino, F., Canale, G. and Sathujoda, P. (2021), "The effect of manufacturing defects on the high-cycle fatigue of electron-beam-welded Ti-6Al-4V titanium alloy: experimental and numerical analysis", Multidiscipline Modeling in Materials and Structures, Vol. 17 No. 4, pp. 796-813. https://doi.org/10.1108/MMMS-09-2020-0230