Numerical and experimental investigation of sintering deformation of brazing powder compacts

摘要

A modified sintering model was presented to analyze the deformation behaviors of brazing powder compact throughout the whole sintering process, both the thermal-mechanical plastic deformation and metallic alloying were implemented as sintering driving forces in the numerical simulation by the sintering model. Ag-Cu-Sn brazing powder compacts were prepared by electromagnetic compaction technique and sintered at different temperature, the simulated deformations were in reasonable agreement with the experimental deformations. Deformation analysis with different relative density was conducted by the sintering model to reveal the volume expansion mechanism and volume shrinkage mechanism throughout the whole sintering process, it was indicated that the sintering warpage or cracks are prominently related to relative density gradients, and the higher relative density of brazing powder compacts is beneficial to sintering densification. At last, the deformation behaviors of brazing powder compacts with three typical shapes were numerically predicted to provide guidelines for tool design and sintering process optimization.