A Simplified Layer-by-Layer Model for Prediction of Residual Stress Distribution in Additively Manufactured Parts

Abstract

With the improvement in technology, additive manufacturing using metal powder has been a go-to method to produce complex-shaped components. With complex shapes being printed, the residual stresses (RS) developed during the printing process are much more difficult to control and manage, which is one of the issues seen in the field of AM. A simplified finite element-based, layer-by-layer activation approach for the prediction of residual stress is presented and applied to L-shaped samples built in two different orientations. The model was validated with residual stress distributions measured using neutron diffraction. It has been demonstrated that this simplified model can predict the trend of the residual stress distribution well inside the parts and give insight into residual stress evolution during printing with time for any area of interest. Although the stress levels predicted are higher than the measured ones, the impact of build direction on the development of RS during the building process and the final RS distributions after removing the base plate could be exploited using the model. This is important for finalizing the print orientation for a complex geometry, as the stress distribution will be different for different print orientations. This simplified tool which does not need high computational power and time can also be useful in component design to reduce the residual stresses.

Mechanical Testing of Selective-Laser-Sintered Polyamide PA2200 Details: Analysis of Tensile Properties via Finite Element Method and Machine Learning Approaches

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A method for rapid estimation of residual stresses in metal samples produced by additive manufacturing

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Selective Laser Sintering Induced Residual Stresses: Precision Measurement and Prediction

“…Neutron diffraction is a widely used technique for measuring residual stresses deep within a material by detecting the diffraction of an incident neutron beam [33,34]. ENGIN-X, a dedicated neutron source engineering science facility at ISIS, Oxfordshire, is optimised for the measurement of strain, and thus stress, deep within a crystalline material, using atomic lattice planes as an atomic 'strain gauge'; based on a time-of-flight (TOF) technique.…”