Study of the structure and mechanical properties of vertical walls printed using the GMAW method

Employees from the Laboratory of Physical Mesomechanics and Non-Destructive Testing Methods, the Laboratory of Mechanics of Polymer Composite Materials and the Laboratory of Local Metallurgy in Additive Technologies of the Institute of Physics and Mathematics of Applied Mathematics SB RAS conducted a study of the structure, mechanical properties and features of the deformation behavior of vertical walls printed by wire-arc additive technology in various modes heat input. The results of the work were published in the journal Metals.

3D printing was performed using OK Autrod 13.14 wire on a substrate made of heat-resistant steel 12Х1МФ in standard arc welding (GMAW) mode and in coldArc mode with reduced heat input. Materials manufactured by the additive method demonstrate 40-45% higher strength and 50-70% lower ductility compared to the substrate material. The structure of printed products is non-uniform in height and is characterized by reduced microhardness within the boundaries of the layers. These areas were studied using optical microscopy and digital image correlation. An increase in strength and a decrease in ductility of printed materials, compared to a ferrite-pearlite substrate, is associated with the presence of layer boundaries, a high cooling rate and the formation of harder phases (a mixture of acicular and allotriomorphic ferrite). The main difference between the 3D printing modes is that there is less heat accumulation for the wall in coldArc mode. This leads to faster cooling of the steel and the formation of a more dispersed and hard structure. It is concluded that the main factors influencing the conditions for the formation of the structure (martensitic, bainite or ferritic), the height and quality of the wall surface, as well as the mechanical properties of the printed product are the cooling rate and the level of heat input.

The work was carried out within the framework of the state assignment of the Institute of Physical Problems and Problems of the Siberian Branch of the Russian Academy of Sciences (projects FWRW-2021-0009 and FWRW-2021-0010).

I.V. Vlasov, A.I. Gordienko, A.V. Eremin, V.M. Semenchuk, A. E. Kuznetsova. Structure and Mechanical Behavior of Heat-Resistant Steel Manufactured by Multilayer Arc Deposition // Metals 2023, 13, 1375.
https://doi.org/10.3390/met13081375