IN-SITU ENERGY CONTROLLED SELECTIVE LASER MELTING APPARATUS AND METHOD

摘要

An in-situ energy controlled selective laser melting (SLM) apparatus, comprising an SLM forming small-spot light-path device, an additional flat-topped large-spot light-path device, and an SLM forming device. The SLM forming small-spot light-path device and the additional flat-topped large-spot light-path device are disposed on the SLM forming device; a flat-topped large spot for simultaneously scanning is additionally provided; energy below a powder melting point threshold is provided; the powder preheating/solidification rate is controlled; and metal formed is annealed. Also provided is a method for achieving the in-situ energy controlled SLM device. By additionally providing the flat-topped large spot for simultaneously scanning, reducing the temperature gradient, and reducing the internal stress of the forming, phenomenon such as deformation and cracking caused by the stress is reduced; and in addition, because the energy input is lower than the melting point threshold of the material, the original SLM small spot only needs to provide a low energy input to complete the melting of the material, thus preventing undesirable situations such as spatter of the molten pool and generation of micro-pores.