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Conductive heat resistance seam welding (CHRSEW) is a new process developed at Edison Welding Institute for creating butt joints on aluminum sheet. The process uses conventional resistance seam welding equipment, and takes advantage of steel cover sheets on either side of the intended joint. Resulting joints are fusion in character, and can be manufactured at very high welding speeds (∼ 3 to 4 m/min). In this study, the conductive heat resistance seam welding process was extended to some new applications. These included joining a 7075-T6 alloy, and a dissimilar thickness 1- to 2-mm 5754 configuration. The former is generally considered unweldable by fusion methods, and is of considerable interest for aerospace applications. The latter is representative of a tailor welded blank for automotive applications. Resulting welds were evaluated using metallurgical examinations and mechanical testing.

Weldability study has been performed on Polypropylene (PP) and PC/ABS samples to investigate how the paint layer along the weld joint affects the vibration weldability. The plastic used for this study were PP representing semicrystalline thermoplastics and PC/ABS representing amorphous thermoplastics. Both resins were molded to generate sample plaques for the study. Design of Experiment (DOE) studies were initially conducted with unpainted plaques and then repeated with the painted plaques for comparison. Optimal welding parameters were determined through DOE and the maximum weld strength under optimized welding conditions were determined and compared. Following each DOE, a regression analysis, using the weld strength as a response, was performed.

An experimental evaluation to systematically study a hot air cold stake joining process was conducted with injection molded samples. Twelve material combinations consisting of six stud plate materials were matched with two hole plate materials (GDT 6400 and 18% talc filled PP). Seven stud designs with variations in size and geometry were used for each material combination. A proper heating temperature was first determined by heat characterization trials. Different heating times and stake heights were studied in the staking experiments. Pull tests were conducted to determine the strength of the joints and their failure mode. Results showed that material characteristics, material combinations, and process parameters all could contribute to variations in pull strength and different failure modes.