The paper presents the impact of a surface treatment (an aluminizing process) on the microstructure and tensile strength of the nickel superalloy IN 718 produced by Selective Laser Melting (SLM). The aluminizing process was carried out by means of chemical vapor deposition with the participation of AlCl₃ vapors, in a hydrogen atmosphere as the carrier gas The microstructure of the nickel superalloy IN 718 after 3D printing and thermo-chemical treatment was observed through a optical microscope and an electron scanning microscope. X-ray diffraction made it possible to analyze the phase composition and to determine the residual stresses (sin²Ψ method). Moreover, it was found that the material had a crystalline texture. A static tensile test was carried out on a Zwick/Roell Z005 testing machine. On the basis of the tests, it was ascertained that, with SLM and an appropriate selection of technological parameters, it is possible to obtain a nickel superalloy IN 718 characterized by a fine column microstructure and crystal dendrites. The samples of the nickel superalloy IN 718 produced featured a high strength, similar to that of nickel superalloy IN 718 produced by conventional methods. It was also shown that an aluminizing process carried out by the CVD method makes it possible to attain an intermetallic layer mainly comprised of a AlNi phase characterized by compressive residual stresses. The tensile strength tests proved that the aluminizing process reduced the strength of the nickel alloy IN 718.

本文介绍了表面处理（渗铝工艺）对通过选择性激光熔融（SLM）生产的镍超合金IN 718的组织和拉伸强度的影响。镀铝过程是在Al2 ₃蒸气的作用下，在氢气气氛中以载气通过化学气相沉积法进行的。通过光学显微镜观察了3D打印和热化学处理后的镍超合金IN 718的微观结构。和电子扫描显微镜。X射线衍射可以分析相组成并确定残余应力（正弦²Ψ方法）。此外，发现该材料具有晶体织构。在Zwick / Roell Z005试验机上进行静态拉伸试验。在试验的基础上，可以确认，与SLM和工艺参数的适当选择，能够获得718一镍基超合金，其特征在于细柱微观结构和树枝状晶体突起。所生产的镍超级合金IN 718的样品具有高强度，类似于通过常规方法生产的镍超级合金IN 718的样品。还显示出通过CVD方法进行的渗铝处理使得可以获得金属间化合物层，该金属间化合物层主要由特征在于压缩残余应力的AlNi相组成。