Numerical simulation method for anisotropic mechanical behavior based on dislocation dynamics
In order to study the anisotropic mechanical behavior of materials in wire arc additive manufacturing(WAAM),the temperature field during the wire arc additive manufacturing process is simulated using a double ellipsoid heat source model in this paper.A Monte Carlo model is established to simulate the microstructural changes in the additive layer.A crystal plasticity model is employed to characterize the influence of grain morphology on the mechanical behavior,which is used to form modified dislocation density model revealing the anisotropic mechanical behavior based on grain morphology in WAAM.The obtained results are consistent with experimental data.The mechanical performance of WAAM components in the build height direction is significantly lower than arc scanning direction.When the ratio of grain size between the build height direction and the arc scanning direction reaches 7.5 mm/1.3 mm,the yield strength ratio reaches 787.8MPa/865.2 MPa.Titanium alloys exhibit obvious material softening at temperatures above 600 ℃ due to grain spheroidization.
wire arc additive manufacturingdislocation dynamicsMonte Carlo modelcrystal plasticity modelmechanical properties
万方数据
维普
