Numerical Simulation Of Transient Temperature Field In Laser Direct Forming Process

The technology of metal parts fabricated by Laser Direct Forming is a new type technology by accumulation and scatter, which not only is a technology in common usage in the Rapid Manufacturing, but also is the mainly used technology in the Rapid Manufacturing of metal parts. Rapid Manufacturing and Rapid Prototyping are considered to be a key breakthrough for first time. Rapid Manufacturing and Rapid Prototyping have influence nearly over emergence of Numeric Control Technology.Distinct from traditional machining process, metal parts can be built layer by layer according to layer information from a virtual three-dimensional model in Laser Direct Forming processing. The numerical simulation of temperature field,thermal-stress field and displacement field of metal part is significant research contents in new material field of our country's 973 project.In this dissertation, numerical simulation of temperature field, thermal-stress field and displacement field of metal part are researched, and the following research works are carried out:(1)This paper handle the finite element model used for simulations of temperature field,thermal-stress field and displacement field appropriately.(2)Treatment of some material physical parameters in High-temperature state used for an effective and precise simulation is gained.(3)On the base of finite element simulation for movable three dimensions transient temperature field model of laser melt pool, using the'birth and death'thermal elements of ANSYS software, the transient temperature field model of 3D wall was established. Real laser direct forming process of the thin wall metal part is simulated in the aspect of thermal property, and the transient temperature field with change on the different process parameters is analyzed, and summed up the law of transient temperature field.(4)Reflection of special technology characteristics in process of thermal-stress field and displacement field simulation is realized. From simulation for the multi-channel laser cladding process, distribution and variation regularities of temperature field,thermal-stress field and displacement field are got by ABAQUS.