Vibration Welding of TPO and Recycled TPO

摘要

Thermoplastic Polyolefins (TPO) have been used extensively in the automotive industry; however, the information about using vibration welding to join these materials is limited. Therefore, the main objectives of this study are to: (1) perform a design of experiments (DOE) on virgin TPO to determine near optimal welding condition and (2) study the effect of regrind concentration on the vibration welded joints. A three-factor (meltdown, pressure, and amplitude) two-level full factorial design of experiments was performed on natural TPO. Additionally, the effect of weld time, pressure, and amplitude were studied as a function of the regrind concentration. The DOE results indicated that the welding time was a strong function of the vibration amplitude, and that the weld strength was not sensitive to the welding parameters used in this study. The maximum joint strength for a virgin T-joint sample was 60% of the base material strength. In addition, high regrind concentration reduced joint strength by as much as 20%. All regrind materials preferred longer welding time. The weld pressure did not affect the joint strength significantly for the regrind materials. All the regrind materials showed highest joint strength when 1.5mm peak-to-peak vibration amplitude was used.