Thermoplastic composites of polylactic acid (PLA)-hydroxyapatite (HAp)-chitosan (CS) (in 91-8-1% weight proportion) is one of the acceptable composition/proportions for preparation of biomedical scaffolds (printed by fused deposition modeling (FDM)) in tissue engineering applications. But hitherto, little has been reported on the repair of PLA-HAp-CS based orthopedic scaffolds, especially in case of minor surface cracks observed post-surgery (maybe because of residual stresses/accident, etc.) from mechanical, thermal, in-vitro, in-vivo, and morphological analysis viewpoint. In this study, the 3D printed scaffolding structures of PLA-HAp-CS (3D printed on FDM) were further joined by friction stir spot welding (FSSW) process for minor repairs (such as surface cracks). The joints formed by the FSSW process were subjected to mechanical, thermal, cytotoxicity (by in-vitro, in-vivo analysis) and morphological analysis. The study results suggest that joints prepared using the consumable tool in FSSW have good mechanical, thermal stability, a good range of biocompatibility, and suitable tissue engineering applications. For FSSW of 3D printed scaffolding structures of PLA-HAp-CS, 1000 rpm tool rotational speed, 4 mm consumable plunge depth, and 40 s stirring time are the optimized set of process parameters. The results are also supported by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analysis.

聚乳酸（PLA）-羟基磷灰石（HAp）-壳聚糖（CS）的热塑性复合材料（重量比为91-8-1％）是用于制备生物医学支架的可接受的组成/比例之一（通过熔融沉积建模（FDM）打印） ））在组织工程中的应用。但是，迄今为止，关于基于PLA-HAp-CS的骨科支架的修复报道很少，特别是在手术后由于机械，热，内应力观察到较小的表面裂纹的情况下（可能是由于残余应力/事故等）。体外，体内和形态分析观点。在这项研究中，通过摩擦搅拌点焊（FSSW）工艺进一步结合了PLA-HAp-CS的3D打印支架结构（3D打印在FDM上），以进行较小的维修（例如表面裂缝）。通过FSSW工艺形成的接头经过机械，热，细胞毒性（通过体外，体内分析）和形态分析。研究结果表明，使用FSSW中的易耗工具制备的关节具有良好的机械稳定性，热稳定性，良好的生物相容性和合适的组织工程应用。对于PLA-HAp-CS的3D打印脚手架结构的FSSW，最佳的工艺参数是1000 rpm的工具转速，4 mm的可消耗切入深度和40 s的搅拌时间。扫描电子显微镜（SEM）和能量色散X射线光谱（EDS）分析也支持该结果。对于PLA-HAp-CS的3D打印脚手架结构的FSSW，最佳的工艺参数是1000 rpm的工具转速，4 mm的可消耗切入深度和40 s的搅拌时间。扫描电子显微镜（SEM）和能量色散X射线光谱（EDS）分析也支持该结果。对于PLA-HAp-CS的3D打印脚手架结构的FSSW，最佳的工艺参数是1000 rpm的工具转速，4 mm的可消耗切入深度和40 s的搅拌时间。扫描电子显微镜（SEM）和能量色散X射线光谱（EDS）分析也支持该结果。