In situ measurements and thermo-mechanical simulation of Ti–6Al–4V laser solid forming processes. (April 2019)

• Record Type: Journal Article
• Authors: Lu, Xufei; Lin, Xin; Chiumenti, Michele; Cervera, Miguel; Hu, Yunlong; Ji, Xianglin; Ma, Liang; Huang, Weidong
• Is Part Of: International journal of mechanical sciences. Volume 153/154(2019)
• Page Start: 119
• Page End: 130
• Publication Date: 2019-04
• Subjects: Additive manufacturing (AM) -- Laser solid forming (LSF) -- In situ measurements of residual stresses -- Numerical simulation -- Thermo-mechanical analysis; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2019.01.043
• Languages: English
• ISSNs: 0020-7403

Abstract

Highlights: Thermocouples, IR imaging, displacement sensor and DIC system were jointly used to develop a systematic in situ thermo-mechanical field measurement platform. A 3D thermo-mechanical coupled model was experimentally calibrated to study the thermo-mechanical behavior of LSF parts. The thermal and mechanical responses of single-wall coupons under different process parameters were recorded and compared with the numerical models. The effect of different process parameters on the thermo-mechanical fields during LSF process was clarified. Abstract: Residual stresses and distortions are two technical obstacles for popularizing the additive manufacturing (AM) technology. The evolution of the stresses in AM components during the thermal cycles of the metal depositing process is not yet clear, and more accurate in situ measurements are necessary to calibrate and validate the numerical tools developed for its simulation. In this work a fully coupled thermo-mechanical analysis to simulate the laser solid forming (LSF) process is carried out. At the same time, an exhaustive experimental campaign is launched to measure the temperature evolution at different locations, as well as the distortions and both the stress and strain fields. The thermal and mechanical responses of single-wall coupons under different process parameters are recorded and compared with the numerical models. Good agreement between the numerical results and the experimental measurements is obtained. Sensitivity analysis demonstrates that the AM process is significantly affected by the laser power and the feeding rate, while poorly influenced by the scanning speed.