Friction stir welding (FSW) is a solid-state welding technology which is frequently used for welding of thermoplastic and metallic alloys in the automobile and aerospace industries. Polylactic acid (PLA) is a biodegradable thermoplastic polymer. PLA can replace petroleum-based polymer in many applications if the FSW process can be used for welding of PLA-based engineering components. In the present study, FSW process was carried out to join PLA sheets to investigate the influence of input parameters such as tool speed and transverse speed on the tensile strength of the welded specimens using different pin profiles. The tool speeds of 700, 1400, and 2000 rpm and traverse speeds of 20, 30, and 40 mm/min were selected to perform the welding. The pin profiles such as cylindrical, threaded, and conical pins of the tool were used to study their effect on the joint strength and efficiency. Visual inspection of the welded specimens was carried out to find the defects in welding. The temperature that is induced during welding and the load-displacement behavior of the welded specimens were also studied to understand the welding behavior of biodegradable PLA.

中文翻译：

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PLA摩擦搅拌焊的实验研究

搅拌摩擦焊（FSW）是一种固态焊接技术，在汽车和航空航天工业中通常用于焊接热塑性和金属合金。聚乳酸（PLA）是一种可生物降解的热塑性聚合物。如果FSW工艺可用于焊接PLA基工程部件，则PLA可在许多应用中替代石油基聚合物。在本研究中，进行了FSW工艺以连接PLA板，以研究使用不同销钉轮廓的输入参数（例如工具速度和横向速度）对焊接试样的拉伸强度的影响。选择700、1400和2000 rpm的工具速度以及20、30和40 mm / min的横向速度进行焊接。销轮廓，例如圆柱，螺纹，使用工具的锥形销钉研究其对接头强度和效率的影响。目视检查焊接试样，以发现焊接缺陷。还研究了焊接过程中引起的温度和焊接试样的载荷-位移行为，以了解可生物降解的PLA的焊接行为。