Analytical model for temperature prediction in friction stir–assisted incremental forming with synchronous bonding of dissimilar sheet metals

Abstract

In the present work, a novel process of friction stir–assisted incremental forming with synchronous bonding of dissimilar sheet metals DC05 and AA5052-H32 has been conducted. The separate dissimilar sheet layers are bonded together to become a laminate sheet with a part simultaneously fabricated by incremental forming. Since the temperature level is a great concern to affect the formability, an analytical heat generation and transfer model is established for temperature prediction combined with different process parameters. Iterative formulae are implemented and the numerical results are obtained to reflect the evolution of maximum temperature during the whole processing period. It is found that larger step down, rotational speed, and forming angle with lower feeding rate will significantly cause higher process temperature, which proves that the proposed model satisfies the need of a prior of the process window. Micro IMC distribution is experimentally measured at different positions to verify the effect of temperature, which also shows good applicability. The proposed temperature prediction model is also valuable for other incremental sheet forming processes with high-speed tool rotation.