Unveiling the Residual Stresses, Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint

B. Mehdi (1) , R. Badji (2) , V. Ji (3) , B. Alili (1) , D. Bradai (1) , W. Bedjaoui (2) , Frédéric Deschaux-Beaume (4) , F. Brisset (3)

1 USTHB - Université des Sciences et de la Technologie Houari Boumediene = University of Sciences and Technology Houari Boumediene [Alger]
2 CRIT - Research Center in Industrial Technologies
3 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
4 AS - Assemblages Soudés

In this work, the micromechanical properties, crystallographic texture, welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4 V alloy tungsten inert gas weld joint. It was found that the welding process affected the Young modulus and microhardness values in both α and β phases in the different regions of the weld joint. The highest microhardness and Young modulus values of α phase were recorded in the heat-affected zone, whereas the highest values of these characteristics for the β phase were found in the fusion zone (FZ). The change in the micromechanical properties was accompanied by a change in the crystallographic texture components of the dominant α phase from (0001) < 10-10 > and (11-20) < 10-10 > components in the base material to (10-10) < 11-20 > and (11-20) < 3-302 > components in the FZ. The introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances.

Mots clés: Ti-6Al-4 V; Tungsten inert gas (TIG) weld; Residual stress; Local mechanical properties; Crystallographic texture

Domaines: Mécanique des structures [physics.class-ph]

B. Mehdi, R. Badji, V. Ji, B. Alili, D. Bradai, et al.. Unveiling the Residual Stresses, Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint. Acta Metallurgica Sinica, 2021, 34 (7), pp.997-1006. ⟨10.1007/s40195-020-01183-0⟩. ⟨hal-03344178⟩