| dc.description.abstract | Abstract. Aluminum alloy 2219 (AA 2219) is the preferred material for spacecraft structural components due to its excellent strength, temperature adaptability, and corrosion resistance. Additive friction stir deposition (AFSD) is a novel solid-phase additive manufacturing technology that can enable avoiding the cracks and defects caused by melting and re-solidification inherent in traditional additive methods. In the AFSD process, the temperature in the deposition region is one of the key factors influencing manufacturing quality. Based on the AFSD heat generation principle and deposition mechanism, this study established a multilayer iterative heat source model for the feeding and traveling stages. The results indicate that along the longitudinal direction, the feeding region can be categorized into three distinct regions, namely the high-temperature region, the depositional region, and the transitional region. The temperature difference between these regions increases with an increasing number of deposit layers. In the traveling region, it can be divided into the behind region, the central region, and the front region. The temperature difference within each layer is essentially consistent. The temperatures measured in both regions along the transverse direction are symmetrically distributed. The temperatures in the feeding region display an 'M'-shaped distribution pattern, while those in the traveling region exhibit an inverted 'V'-shaped distribution. Additionally, peak temperatures across all regions demonstrate an upward trend correlating with increased rotational speeds and deposition rates. These findings provide a theoretical foundation for further investigations into temperature field dynamics during AFSD of AA 2219. | |
