Abstract
The reported strengths of industrial hot melt adhesives are in the range of 500-1000 psi when assessed gravimetrically, or 3.4-6.9 MPa. The strongest laser welds using ICG/albumin paste as a solder and laser exposures of 20-100 s have breaking strengths in the range of 400 to 600 N/cm2, or 4-6 MPa. The threshold tensile pressure for laser-induced cavitation of body water, which has particulates to act as nucleation sites, is about 10 bar or 1 MPa. For 10% and 20% collagen gels, the threshold tensile pressures for cavitation are about 28 and 46 bar, or 2.8 and 4.6 MPa, respectively. Hypothesis: Tensile-pressure-induced weld failure and laser-induced cavitation share a common mechanism of void initiation and growth, thereby explaining their similar pressure thresholds. Hypothesis for mechanism: Conservation of density and volume requires that solder flows inward radially when the two adjoined surfaces are pulled apart. When the solder cannot flow sufficiently fast to match the rate of surface separation, void volumes form to allow the surfaces to separate. Such void formation is comparable to cavitation that has a known threshold tensile pressure for onset.
Original language | English (US) |
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Pages (from-to) | 195-201 |
Number of pages | 7 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 4609 |
DOIs | |
State | Published - 2002 |
Externally published | Yes |
Event | Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems XII - San Jose, CA, United States Duration: Jan 19 2002 → Jan 22 2002 |
Keywords
- Adhesives
- Cavitation
- Laser welding
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering