Understanding the effect of non-conventional laser beam geometry on material processing by finite-element modelling

Abstract

The temperature distribution inside the material is of prime importance in laser material processing. Optimization of laser processes requires control over this temperature distribution in order to achieve the desired outcomes by manipulating heating/cooling rates and thermal gradients. So far, most of the laser material processing has been carried out by using circular and rectangular beam geometries with variations in laser power, spot size, and scanning speed. However, variations in these parameters are often limited by other processing conditions and it is not always possible to change, e.g. the scanning speed or laser power. One possible method of varying the temperature distribution, and hence the heating/cooling rates and thermal gradients, is to modify the geometry of laser beams. It has been shown that non-conventional laser beam geometries can be effectively employed for laser processes such as surface heating, transformation hardening, forming, melting of metallic materials, and laser cutting. This article presents a review of non-conventional laser beam geometries that can be utilized to improve and/or optimize many laser material processes. Some examples of laser material processing that have been previously studied in detail are briefly discussed.

Finite element modelling of substrate thermal distortion in direct laser additive manufacture of an aero-engine component

“…The non-linear structural analysis carried out was to find this thermal distortion and this was estimated using an elastic FE solution. 32…”

Analysis of the geometric effect on the forming accuracy in laser forming

“…A large number of theoretical, experimental, and numerical investigations have been carried out to understand the deformation behaviour of a plate which is caused by laser forming, and much important progress has been realized [5][6][7][8][9][10][11]. The aim of laser forming is normally to achieve bending deformation of a plate.…”

“…As a flexible and dieless forming technique, laser metal forming has extensive application in the shipbuilding, automobile, and aerospace industries [1][2][3][4]. A large number of theoretical, experimental, and numerical investigations have been carried out to understand the deformation behaviour of a plate which is caused by laser forming, and much important progress has been realized [5][6][7][8][9][10][11]. The aim of laser forming is normally to achieve bending deformation of a plate.…”

Numerical investigation of temperature field of different mechanisms in laser forming

“…Laser forming is a flexible and dieless forming process realised by introducing non-uniform thermal stresses into the surface of a work piece with a laser beam. As a hot accumulation forming method, in comparison with conventional metal forming processes, requires no dies or external forces, and it is particularly suitable for forming hard and brittle materials, which is a promising technology in manufacturing such as in the shipbuilding, automobile, microelectronics and aerospace [1][2][3] industries, and in low volume production.…”