Analytical and numerical modeling of light scattering in composite transmission laser welding process

The Clearweld process is a through-transmission laser welding process that offers engineers unique design options. The absorbing material that enables the welding to be carried out is available as a coating or compounded into a resin. The purpose of this paper is to provide an overview of through-transmission laser welding and to describe the Clearweld process. Design considerations were included to assist engineering in the design of parts and joint geometries that are compatible with through-transmission laser welding. Guidelines for selecting coatings or dye compounding were also provided. An experiment comparing Clearwelding with solvent bonding of poly(methyl methacrylate) to polysulphone proved Clearweld strengths to be higher than solvent bonding.

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Numerical Modeling of Thermoplastic Films in a Laser Welding Process

Manufacturing Engineering and Materials Handling, Parts A and B ◽

10.1115/imece2005-81097 ◽

2005 ◽

Cited By ~ 1

Author(s):

Richard A. Whalen ◽

Gregory J. Kowalski

Keyword(s):

Laser Welding ◽

Welding Process ◽

Surface Cooling ◽

Simulation Code ◽

Transmission Laser Welding ◽

Lap Welding ◽

The Relationship ◽

Thermo Physical Properties ◽

Laser Welding Process ◽

Moving Layers

A numerical simulation code is used to investigate the size of the heat affected zone (HAZ) and the onset of thermal damage in a short pulsed transmission laser welding process. The welding process involves the lap welding of two thin 30 microns thick, moving layers, of thermoplastic films. The investigated welding conditions are transparent material over a semi-transparent or opaque material and two transparent materials over a reflective backing. The results provide temperature profiles that illustrate the relationship between; surface cooling, laser intensity, velocity feed rates and material thermo-physical properties.

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Thermal Modeling in Composite Transmission Laser Welding Process: Light Scattering and Absorption Phenomena Coupling

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.611-612.1560 ◽

2014 ◽

Vol 611-612 ◽

pp. 1560-1567 ◽

Cited By ~ 5

Author(s):

André Chateau Akue Asseko ◽

Benoît Cosson ◽

Fabrice Schmidt ◽

Rémi Gilblas ◽

Yannick Le Maoult ◽

...

Keyword(s):

Light Scattering ◽

Laser Welding ◽

Analytical Model ◽

Three Dimensional ◽

Welding Process ◽

Thermoplastic Composites ◽

Field Calculation ◽

Laser Beam Intensity ◽

Welding Interface ◽

Laser Welding Process

In previous studies [1, , we have presented a detailed formulation of a macroscopic analytical model of the optical propagation of laser beams in the case of unidirectional thermoplastic composites materials. This analytical model presented a first step which concerns the estimation of the laser beam intensity at the welding interface. It describes the laser light path in scattering transparent composites (first component) by introducing light scattering ratio and scattering standard deviation. The absorption was assumed to be negligible in regard to the scattering effect. In this current paper, in order to describe completely the laser welding process in composite materials, we introduce the absorption phenomenon in the model, in the absorbing material (second component), in order to determine the radiative heat source generated at the welding interface. Finally, we will be able to perform a three dimensional temperature field calculation using a commercial FEM software. In laser welding process, the temperature distribution inside the irradiated materials is essential in order to optimize the process. Experimental measurements will be performed in order to valid the analytical model.

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Numerical Simulation of Thermoplastics in a Short Pulsed Laser Welding Process

Manufacturing Engineering and Textile Engineering ◽

10.1115/imece2006-14125 ◽

2006 ◽

Author(s):

Richard A. Whalen ◽

Gregory J. Kowalski

Keyword(s):

Numerical Simulation ◽

Laser Welding ◽

Laser Intensity ◽

Welding Process ◽

Thin Layers ◽

Simulation Code ◽

Transmission Laser Welding ◽

Lap Welding ◽

Thermo Physical Properties ◽

Laser Welding Process

A numerical simulation code is developed and used to investigate the differences in thermal behavior and the size of the heat affected zone (HAZ) in a short pulsed transmission laser welding process (>0.5 ps (1/e2)). The numerical model uses both a Fourier and Hyperbolic thermal model. The welding process involves the lap welding of two thin layers of thermoplastic films. The investigated welding conditions are transparent material over a semi-transparent or opaque material. The results provide temperature profiles that illustrate the differences between the predicted temperatures of the two thermal models as well as the effects of laser intensity and material thermo-physical properties.

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