Numerical Modeling of Thermoplastic Films in a Laser Welding Process

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.

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 ◽

Lap Welding ◽

Thermo Physical Properties ◽

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.

THROUGH TRANSMISSION LASER WELDING PROCESS OPTIMIZATION FOR SEMICRYSTALLINE AND AMORPHOUS PLASTICS

MM Science Journal ◽

10.17973/mmsj.2020_11_2020042 ◽

2020 ◽

Vol 2020 (4) ◽

pp. 4119-4123

Author(s):

Martin Seidl ◽

Jiri Safka ◽

Lubos Behalek ◽

Iva Novakova

Keyword(s):

Laser Welding ◽

Process Optimization ◽

Welding Process ◽

In-situ infrared thermography measurements to master transmission laser welding process parameters of PEKK

Optics and Lasers in Engineering ◽

10.1016/j.optlaseng.2018.02.016 ◽

2018 ◽

Vol 106 ◽

pp. 94-104 ◽

Cited By ~ 2

Author(s):

M. Villar ◽

C. Garnier ◽

F. Chabert ◽

V. Nassiet ◽

D. Samélor ◽

...

Keyword(s):

Laser Welding ◽

Infrared Thermography ◽

Process Parameters ◽

Welding Process ◽

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

Clearweld: welding of clear, coloured, or opaque thermoplastics

10.1243/095440705x34775 ◽

2005 ◽

Vol 219 (9) ◽

pp. 1069-1074 ◽

Cited By ~ 6

Author(s):

N M Woosman ◽

L P Frieder

Keyword(s):

Laser Welding ◽

Methyl Methacrylate ◽

Process Design ◽

Welding Process ◽

Design Considerations ◽

Absorbing Material ◽

Solvent Bonding ◽

Design Options ◽

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.

Thermal Defocussing Criteria for a Laser Welding Process

Manufacturing Engineering and Materials Handling Engineering ◽

10.1115/imece2004-59626 ◽

2004 ◽

Cited By ~ 1

Author(s):

Gregory J. Kowalski ◽

Richard A. Whalen

Keyword(s):

Laser Beam ◽

Laser Welding ◽

Phase Change ◽

Heat Affected Zone ◽

Solid Phase ◽

Welding Process ◽

Index Of Refraction ◽

Simulation Code ◽

Collimated Beam ◽

A numerical simulation code is developed to study the significance of refraction effects (beam self-focussing or defocussing) of a laser during a laser welding process. Relationships between the size of the heat affected zone (HAZ), the melt zone and the laser beam parameters are investigated for a short pulsed laser welding process. The solution method includes the thermally stimulated nonlinear optical effects caused by the temperature dependent index of refraction, as well as the step change in surface reflection that occurs due to the liquid and solid phase change. The interaction of these parameters is investigated to better control the laser manufacturing processes. Difficulties of numerical modeling and the tradeoff between using small nodes to reduce the sawtooth behavior in the phase change model and computer run times that are consistent with real time control are discussed. The results indicate that there are no significant refraction affects of the laser beam and that the heat affected zone is approximately 6% larger for a collimated beam input as compared to a gaussian beam input. Peak temperatures are lower for the collimated beam.