Modeling of laser deposition and repair process

Abstract

Laser aided deposition is a material additive based manufacturing process via metallurgically bonding the deposited material to the substrate. Due to its capability to bond various materials together, it becomes an attractive technology for part repair in small scale. However, the details of the process remain an active area for research because of the complicated interactions involved. In this study, a mathematical model was established to investigate thermal and mass transportation phenomena, which include substrate melting and solidification as well as the powder heating process. Affected by the powder injection, the melt pool surface keeps fluctuating during the process and dynamic evolution of the melt pool shape is tracked by using the level set method. Melt pool shape and energy balance at liquid–vapor and solid–liquid interfaces are taken into account in the model. A typical hole repair process based on material deposition technology is presented. The detailed process together with the temperature distribution were simulated. The simulation results of the melt pool length and peak temperature are validated for the laser deposition process through the measurements on the melt pool geometry and surface peak temperature by the complementary metal–oxide–semiconductor camera and dual-wavelength temperature sensor.

Modeling the Influence of Process Parameters and Additional Heat Sources on Residual Stresses in Laser Cladding

“…A series of closed models, that regard most of the interrelated processes in laser cladding such as preheating of the powder particles crossing the laser beam and the related beam attenuation, the powder resorption by the melt pool, and the evolution of temperature field and bead geometry, were published during the last few years (Ref [21][22][23][24][25][26][27][28][29][30][31].…”

Modeling of coaxial powder flow for the laser direct deposition process

“…In the studies that considered both powder concentration and laser heating process, some simplifying assumptions about the powder flow were made and its structure was predefined [15][16][17][18][19][20][21][22][23]. Assuming an average particle radius, powder flow temperature from coaxial nozzles was calculated and also experimentally investigated by Vetter et al [15] and Pinkerton [16].…”

Freeform Laser Consolidated H13 and CPM 9V Tool Steels

“…A lot of investigations have been reported to promote these processes for TDM materials development and rapid manufacturing by direct fabricating functional shapes or by enhancing, repairing, or re-configuring existing TDM with affordable cost [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. However, it is also realized that some of these processes might only produce a ''near-net'' shape with rough surface finish and low-dimensional accuracy [4,5,22,23] and, thus, post-machining is a must, which, more or less, could diminish the attractiveness of the processes.…”