Numerical and experimental studies on the effect of varied beam diameter, average power and pulse energy in Nd: YAG laser welding of Ti6Al4V
Journal: Infrared Physics & Technology
Author: Masoud Afrand
The study of heat transfer during melting and solidification phenomena is significant important in many engineering applications such as welding, crystal growth, metalworking, casting, etc. In this paper, asymmetric temperature distribution in moving titanium (Ti6Al4V) exposed to the concentrated welding was investigated. At first, a numerical simulation was carried out to solve the governing equations by using the initial and boundary conditions. To validate the numerical results, a laboratory system was launched and the Ti6Al4V plate with known properties was exposed to the laser welding. By changing the various parameters such as heat flux, pulse duration, beam diameter, average power and pulse energy, the experimental and numerical results were compared. The results showed that the increasing the melt pool dimensions (width and depth), due to an increasing in the average power, had a more significant effect than the decrease in laser pulse diameter. Also, the penetration depth was increased with increasing the pulse energy. The model prediction error was between 5 and 14%, which in the most of the results, the difference between numerical and experimental values are lower than 8%. According to the agreement of numerical simulation with the experimental results, it became evident that the numerical results could be used to predict the geometry of the melt pool dimensions for other materials, thereby saving the cost of materials, manpower and preparation and testing operations.