Tailor welded blank sheets made of friction stir welding (FSW) process have found many applications in aerospace, automobile, marine, and other industries. In the present study, two different aluminum alloys AA5083-O and AA6082-T6 having 2 mm thickness were used. This research presents the multi-responses optimization of process parameters, i.e., rotation speed (R), travel speed (T), and shoulder diameter (S) in the FSW process using response surface methodology (RSM) based on gray relational analysis (GRA) coupled with principal component analysis (PCA) technique. For the optimization of the process, the face-centered central composite design technique with minimal design was used to get the optimum level of the parameter. The objective of this paper is to find out the optimum level of the process parameters which yields the maximum responses, i.e., ultimate tensile strength, total elongation, yield strength, dome height, and microhardness value. ANOVA technique was used to ensure the significant contribution of the individual and the combination of process parameters. The confirmatory run analyzed the optimized process parameters, and the experimental result was observed within 2.6% of error agreement with predicted values. GRA determined the optimum value of the input parameter with the PCA technique, a hybrid approach. The optimum value of R, T, and S was found at 1900 rpm, 40 mm/min, 12 mm, respectively. The microstructural study of variation in grain structure across the different zones of the FSW region was examined and tested by scanning electron microscope. The microhardness and formability tests for the optimized parameters were carried out. This research reveals that the multi-response optimization problem can be easily solved through RSM based GRA-PCA approach.

由搅拌摩擦焊 (FSW) 工艺制成的定制焊接坯板在航空航天、汽车、船舶和其他行业中得到了广泛的应用。在本研究中，使用了厚度为 2 毫米的两种不同的铝合金 AA5083-O 和 AA6082-T6。本研究提出了工艺参数的多响应优化，即转速 ( R )、行驶速度 ( T ) 和肩部直径 ( S) 在 FSW 过程中使用基于灰色关联分析 (GRA) 和主成分分析 (PCA) 技术的响应面方法 (RSM)。为优化工艺，采用面心中心复合设计技术，最小化设计，得到参数的最佳水平。本文的目的是找出产生最大响应的工艺参数的最佳水平，即极限抗拉强度、总伸长率、屈服强度、圆顶高度和显微硬度值。方差分析技术用于确保个体的显着贡献和工艺参数的组合。验证性运行分析了优化的工艺参数，并在与预测值相差2.6％的误差范围内观察到了实验结果。GRA 使用 PCA 技术（一种混合方法）确定输入参数的最佳值。的最佳值R、T和S分别在 1900 rpm、40 毫米/分钟和 12 毫米下测得。通过扫描电子显微镜检查和测试了 FSW 区域不同区域晶粒结构变化的微观结构研究。对优化参数进行了显微硬度和成形性测试。该研究表明，通过基于 RSM 的 GRA-PCA 方法可以轻松解决多响应优化问题。