激光熔丝增材制造过程气孔演化行为研究

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Abstract： In order to reveal the evolution mechanism of pores in the laser wire aditive manufacturing （LWSM） process and achieve efective regulation of pore defects，anumerical model of stomatal evolution was established in this study，the effect of laser power on porosity evolution during laser fuse additive manufacturing was systematically analyzed，further explored the pore escape mechanism.The resultsshow： As the laser power increases，the velocity field inside the molten poolis enhanced，forminga“vortex”，this prevents bubbles from escapingthe molten pool， eventuall pores are formed in the deposited layer.The bubbles in the molten pool are mainly affected by buoyancy， thrust generatedby the flow of the molten pool， viscosityof the liquid metal and gravity.The thrust generated by the molten poolflow has different effects at different stages of bubble escape，Gravityand viscous drag act are hindering forces，while buoyancy and generate molten pool flow bythe upward thrust to promote the escape of bubbles from the molten pool. The research results provide a theoretical basis for optimizing process parameters and reducing porosity defects in laser fuse additive manufacturing.

Keywords：additive manufacturing;pore; laser power; numerical simulation

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近年来，随着各个领域的快速发展，精密化和轻量化钛合金构件的需求量激增[1]。（剩余7685字）