重叠系数对电弧增材制造Al-Mg合金的结构和力学性能的影响

Investigation of the overlapping coefficient impact on the structure and mechanical properties of Al-Mg alloy obtained by wire arc additive manufacturing

本文研究了直接电弧生长制备Al-Mg合金厚壁样品的结构特征和力学性能。由于该制备方法具有高生产率和低成本的优点,在近几十年来得到了特别的关注。该工艺的高生产率使电弧增材制造适用于生产大壁厚的材料。通过改变重叠系数,可以实现厚壁零件的准确成形,并得到指定的尺寸。重叠系数的变化导致材料尺寸、形态以及金属间化合物分布的变化,并影响其力学行为。本文考虑了不同重叠系数下晶粒结构形成的特征,金属间化合物成分及厚壁材料力学性能。发现样品中有两种金属间化合物Mg2Si和Al6(Fe,Mn),它们的大小和形态随重叠系数的变化而改变,从而导致材料力学性能的各向异性。当重叠系数为0.4时,其抗拉强度、屈服强度和伸长率均达到最高值,分别为319 MPa,150 MPa和16.1%。

The work is devoted to the study of structural features and mechanical properties of thick-walled samples of Al-Mg alloy got by direct arc growth.This method has attracted particular attention in recent decades,mainly because of its high productivity and low cost.The high productivity of the process makes the wire arc additive manufacturing technology suitable for the production of large wall thicknesses.It is possible to achieve the correct formation of thickwalled elements and to get the specified dimensions by changing the overlap coefficient.It is important to consider that changes in the overlapping coefficient led to changes in size,morphology,as well as the intermetallic distribution,which will affect the mechanical behavior of the samples.The paper considers the features of grain structure formation,phase intermetallic components and their influence on the mechanical properties of thick-walled samples got at different overlapping coefficients.Two types of intermetallic compounds Mg_(2)Si and Al6(Fe,Mn)were identified in the sample.Their size and morphology differ in relation to the overlap coefficient.As a result,the samples demonstrate anisotropy of mechanical properties.The highest values of tensile strength,yield strength and elongation obtained at 0.4 overlapping coefficient and were 319 MPa,150 MPa and 16.1%,respectively.