Powder bed fusion (PBF) is an additive manufacturing (AM) technique commonly used to manufacture metallic components. External geometry of parts printed by PBF process can be extended by regular processes, namely, laser cladding and spraying powder metal. But these methods have disadvantages such as increased heat-affected zone (HAZ) and extended deficiencies like cracks and pores, whereas samples produced with directed energy deposition (DED) exhibited strong metallurgical bonding and has reduced HAZ due to least dilution. The present work investigates the properties of stainless steel 316L (SS316L) sandwich structure built by combining PBF and DED process. The external geometry of the SS316L samples built by PBF was extended by using DED technique. Metallurgical and mechanical characteristics of DED extended PBF samples were studied. Tensile properties such as percentage elongation and tensile strength were compared for PBF, DED, and SWS (DED extended PBF). It was found that the yield stress for the DED samples, PBF samples, and SWS samples is in the range of 486 MPa, 564 MPa, and 401 MPa. Moreover, the average hardness of the interface portion is found to be 220.5 HV and it is higher than the hardness observed in the PBF and DED regions.

粉末床熔合（PBF）是通常用于制造金属部件的增材制造（AM）技术。通过PBF工艺印刷的零件的外部几何形状可以通过常规工艺扩展，例如激光熔覆和喷涂粉末金属。但是这些方法的缺点是，如热影响区（HAZ）增大以及缺陷（如裂纹和孔隙）扩大，而采用定向能量沉积（DED）生成的样品则表现出较强的冶金结合性，并且由于稀释程度最低而降低了HAZ。本工作研究了结合PBF和DED工艺构建的316L不锈钢（SS316L）三明治结构的性能。通过使用DED技术扩展了由PBF构建的SS316L样品的外部几何形状。研究了DED扩展PBF样品的冶金和力学特性。比较了PBF，DED和SWS（DED扩展PBF）的拉伸性能，例如伸长率和抗张强度百分比。发现DED样品，PBF样品和SWS样品的屈服应力在486MPa，564MPa和401MPa的范围内。而且，发现界面部分的平均硬度为220.5HV，并且高于在PBF和DED区域中观察到的硬度。