Investigating the temperature from friction stir in the SPIF process via an infrared imager

Single point incremental forming (SPIF) is a highly flexible forming process for sheet metal. It has low production costs be-cause the process does not use a die. It is suitable for prototyping and made-to-order production. Currently, the SPIF process employs the concept of heat to increase formability. The idea is to generate heat from friction caused by sliding the tool against the workpiece, called “friction stir”. This research proposed to study the behavior of temperature that occurs when affected by the tool rotation speed and the feed rate, which are both variables affecting friction stir. This research adopted the method of detecting temperature with infrared cameras and online recording data. The camera sensor received data as 8-bit images containing data from 0 to 255. The value of each position represented the temperature level. In this research, the mini-mum-maximum temperature range was set at 80–300 degrees Celsius for forming the hot dipped zinc coat roll steel sheet at a thickness of 0.2 mm using the SPIF process. The variable parameters were the tool rotation speed and feed rate. The tool rotation speed was categorized as high and used no sliding friction with feed rates of 500, 1000, 1500 mm/min. Concerning the results analysis, this study used the relationships between tool rotational speed and feed rate, shown as relative sliding velocity. The results showed with significance that the increase of the maximum temperature in the process corresponded to an increase in relative sliding velocity using a tool rotational speed and feed rate with no relative sliding velocity. The process temperature was close to room temperature. Relative sliding velocity at approximately 6000 and 10000 mm/min caused a maximum temperature of approximately 160–180 and 200–250 degrees Celsius, respectively. Another issue found in the experiment was that not turning the tool reduced the formability of the process.