Queen├ó┬?┬?s University Belfast, UK
Posters & Accepted Abstracts: J Laser Opt Photonics
Currently, micro-joining of plastic to metal parts in medical devices is achieved using medical adhesives, e.g. pacemakers, defibrillators, and neurological stimulators are designed using silicone adhesive to seal the joint between polyurethane connector module and titanium. Nevertheless, the use of adhesive is problematic because it requires a long time to cure and has high tendency to produce leachable products. An alternative for direct joining of plastic to metal without adhesive is therefore required. Laser transmission joining (LTJ) is growing in importance and has high potential to gain the niche in micro-fabrication of plastic-metal hybrid joints for medical device applications. The widely-accepted understanding of LTJ between plastic and metal is that generation and rapid expansion of micro-bubbles at the plastic-metal interface exert high local pressure to press the melted plastic towards the metal surface features during laser processing. This subsequently creates the plastic-metal hybrid joint by mechanisms of mechanical interlocking, chemical and physical bonds between the plastic and metal surfaces. Although micro-bubbles can help promote the mechanical interlocking effect to increase the joint strength, creation of bubble is a random and complex process depending on the complicated interactions between laser intensity, thermal degradation properties of plastic, surface temperature and topographical features of metal. In ideal situation, it is desirable to create the plastic-metal hybrid joint without bubbles. However, the mechanical performance of hybrid joint without bubbles is still unknown. Systematic comparison between the hybrid joints with and without bubbles is lacking in literature. This became the objective of this study.
Journal of Lasers, Optics & Photonics received 279 citations as per Google Scholar report