3D Printing. Structure and Mechanical Properties of Thin-Walled Metal Products

The use of 3D metal printing technology to manufacture thin-walled metal products has a number of well-known advantages that determines the innovativeness of this technology. The study describes the procedure of high-speed additive 3D forming (high-speed 3D steel printing, rapid prototyping) of a conical thin-walled metal product during arc surfacing in a mixture of shielding gases of the 9MnSi5 (DIN) steel wire on a steel disk. Studies of the structure and mechanical properties of selected fragments of the deposited part of the cone show the formation of a uniform ferrite-pearlite structure, which in terms of dimension and distribution has the maximum score of 10 according to ISO 643 standard. A micromechanical test according to ISO/FDIS 145771:2015 standard measures Young's modulus of the deposited part of the cone at the level of 200 GPa, which corresponds to the average value for the base 9MnSi5 (DIN) alloy. Tests of mechanical properties according to ASTM E8 standard show an overall increase in all mechanical characteristics of the deposited part: yield strength is increased by 9.7%, ultimate tensile strength is increased by 1.2%, and relative elongation is doubled. Thus, the unique efficiency of the high-speed 3D steel printing method is shown for manufacturing of thin-walled products.