SAC305 solder's response to gamma radiation environment: IMC layer, XRD characteristics and hardness behavior

This study explores the impact of radiation dose exposure on the characteristics of solder joints, with a focus on the interplay between the intermetallic compound (IMC) layer thickness, X-ray diffraction (XRD) patterns, and hardness of SAC305 solder. By subjecting solder joints to varying gamma radiation doses, we investigate their responses and draw insightful correlations. Microstructural evolution of Sn-Ag-Cu solder alloys induced by gamma radiation were investigated such as the distribution of primary phase beta Sn (ß-Sn) and near eutectic phase, intermetallic compound (IMC) layer thickness and generation of micro-cracks. Characterization and analysis of microstructure were examined via optical microscopy, and X-ray Diffraction analysis. Our findings reveal a direct relationship between radiation dose and IMC layer thickness, as higher doses result in a proportional increase in layer thickness. XRD analysis confirms the presence of characteristic peaks associated with ß-Sn, Ag3Sn, and C116Sns phases, underscoring the structural integrity of the SAC305 solder joints. The mechanical properties of the solder joints exhibit intriguing behaviors with increasing radiation dose. Initial exposure leads to enhanced hardness, suggesting radiation-induced strengthening effects. However, a subsequent decline in hardness occurs as radiation dose is raised up to 500 Gy, possibly indicating a saturation point or radiation-induced softening mechanism. Remarkably, beyond the 500 Gy threshold, hardness begins to rebound as doses reach 5000 Gy and 50000 Gy. This suggests complex interactions between radiation-induced defects and phase transformations within the solder. These findings offer critical insights into the intricate interplay between gamma radiation exposure and the mechanical properties of solder joints. This understanding holds significant implications for designing electronic systems resilient to radiation in high-risk environments.