Efficacy of the distortion compensation method for Selective Laser Melting specimens

Abstract

As industry 4.0 has gained momentum, the need for accurate, fast, and customizable component prototyping and fabrication has risen drastically. Additive manufacturing provides the freedom and capability to fabricate complex and multipurpose components for various applications ranging from aerospace to dental applications. This manufacturing methods’ basic principle is fabricating a component by adding material in layers and selectively melting the powder in a layer-by-layer fashion to complete the component. Additive manufacturing is known to induce thermal stress in the part as the component is repeatedly heated and cooled, leading to defects forming in the component. One of the most frequent defects resulting from thermal stress in additive manufacturing is the deformation of the component. In some instances, the deformation can occur to such an extent that the part will be rendered unusable due to dimensional inaccuracies and resulting in a loss of resources and time. The use of calibrated software and hardware utilized to fabricate additive manufactured components makes it possible to calculate, predict, and compensate for any deformation the component will undergo during and after the fabrication process. This study aims to evaluate the efficacy of the distortion compensation method on selective laser melted specimens. This distortion compensation method is implemented to alter the geometry of the designed component to minimize the deformation of the part. This study consists of three phases, which is essential for successfully implementing the distortion compensation method. The first is the calibration phase, which aims to calculate the corresponding Eigen strain tensor values that will enable the software to predict any deformation that can occur during and after fabrication. After which follows a validation phase to validate the calculated Eigen strain values that resulted from the calibration phase, ensuring the deformation predicted in the simulation correlates with the actual deformation of the part. Lastly, the distortion compensation phase will investigate the efficacy and accuracy of this method to decrease the distortion of components. The findings of this study show a clear and accurate correlation between the theoretical and practical deformation of the samples. A predicted deformation tolerance accuracy of <2% during the simulation phase can be achieved by calibrating the software and hardware. As the distortion compensation algorithm is applied to the geometries, the predicted deformation accuracy decreases to a tolerance of <6%. Although the predicted deformation accuracy of the geometry subjected to the distortion compensation method is lower than the non-distortion compensated geometry, the overall total deformation of the geometry was still decreased by <4%. Thus, the

method of distortion compensation is a promising tool to decrease the distortion of additively manufactured parts.