Discussing of Deformation of Additive Manufacturing due to External Bending

Abstract

Abstract. Default and deformations are some of issues for Additive manufacturing, as known as the 3D printing. When it processes multilayer thin films stacking, this process will introduce higher residual stress that causes deformation. This phenomenon makes the product faulty such as delamination, crack and blisters. The reason could be included ununiformed casting, temperature, cubical contraction etc. However, it is not easily to seem the difference form the films in the present. For ceramic materials, if deformation was existed at interface between layers, the crack would appear after the sintering was completed. For elastic material, the film will be bended, if the structure of product is unstable or the thickness is not thick enough to resist bending. In order to observe the deformation from material, residual stress and external bending must be considered. The purpose of the present study is to find the best approximation of formula for 3D printing and to predict the residual stress for the products. Later, the producing process could be adjusted until the most deformation is eliminated. The methods for present study are considered for two multilayer formulas. One is derived from Hsueh's closed-form, the anther is Timoshenko Theory. The results are combined simulation and experimental for two material and their accuracy is examined. Except considering the effect of the thermal stress, the acceptability of assuming for analyses in the 3D printing system is discussed.