| Summary: | 碩士 === 國立中正大學 === 機械工程系研究所 === 106 === The objective of this study is to develop the dissimilar ultrasonic welding (UW) process for aluminum alloy (Al) and thermoplastic carbon fiber reinforced plastic (TP-CFRP) sheets. The main contents include the design and manufacturing of UW tools, development of Al/Al similar UW process, and development of Al/CFRP dissimilar UW process. For tool development, a UW tool with 10×10 mm diamond-shaped surface texture was designed based on the welding requirements. Next, the modal analysis and harmonic analysis of the UW tool were conducted by the finite element analyses to estimate the harmonic frequency and amplitude of the designed tool. After tool manufacturing, the harmonic frequency and amplitude of the UW tool were obtained and validated by the laser displacement sensor. For Al/Al similar UW process, Al 6061-O sheets were used to understand the relations between three important processing parameters, welding energy, punching force and amplitude, and welding qualities. Then, the parameter analysis and optimization were carried out by the central composite circumscribed (CCC) design tests. The optimal processing parameters were the energy of 3113 J, force of 768 N and amplitude of 100%. For Al/CFRP dissimilar UW process, the previous results were first taken as a reference. The effects of three processing parameters on the welding quality were then studied. Then the welding quality was further improved by surface treatment technology. The good processing parameters were the energy of 1400 J, force of 120 N, amplitude of 100%, and nitric acid surface cleaning.
|
|---|
