Sintered silver is known for its high thermal and electrical conductivity and is considered a promising die attach material for wide bandgap semiconductors at high power. This study investigates the evolution of microstructure and mechanical properties of sintered silver materials during aging in different atmospheres. The study used a combination of experimental methods, including shear tests, scanning electron microscopy, and EBSD, to evaluate the effects of air and nitrogen atmospheres on the reliability of the material. Advanced simulation methods, such as dynamic Monte Carlo and phase field methods, were combined to predict grain growth and void evolution during aging. The results show that air aging accelerates grain growth and pore aggregation, and oxidation is suppressed in a nitrogen atmosphere. These findings provide insights into optimizing the sintering process to improve the long-term stability and performance of sintered silver in semiconductor packaging applications.