Summary: | 碩士 === 國立臺灣大學 === 應用力學研究所 === 99 === A probe tack testing system was built in this study. Unlike peel testing, the probe tack testing eliminates the effect of adhesive carrier. It can measure the characteristics of PSA purely. In this study, the probes were made by silicon wafer instead of stainless steel with the benefits of good surface roughness and flatness. The experimental parameters such as thickness of adhesive, debonding velocity and dwell time are discussed in the research to test the reliability of this system.
Besides, in order to study the growth of cavity, a method of generating single cavity was first proposed. A PMMA particle was introduced as an artificial defect to induce the formation of the single cavity. Furthermore, it was observed that the peak stress σ1p was correlated with the location of particle on adhesive surface. The experiments with different probe diameters (a) and adhesive thickness (h0) were tested. Under the same α, the normalized peak stress was the same for different probe diameter and adhesive thickness. The results show that the dimensionless term α (= a/h0) dominated the debonding mechanism.
Moreover, the effects of probe geometry were discussed. The circular, annular and rectangular probes made of silicon wafer were used. Some had same contact area, the others had same contact perimeter. The results showed that peak stress was affected not only contact area but contact perimeter. Also, the parameter hydraulic diameter Dh was used for annular and rectangular probes to make a good correlation with peak stress
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