At Tomsk Polytechnic University (TPU) (Tomsk, Russian Federation), physicists are working to create hydrogen-resistant products out of titanium alloys based on additive manufacturing. Specifically, the researchers plan to print aircraft parts out of titanium alloys BT6 (Ti–6Al–4V), a widespread material similar to UNS R56200, and BT9 (Ti–6.5Al–3.5Mo–1.5Zr–0.3Si), which is being developed by TPU out of crystalline titanium.
“For the research, we chose these two materials, which have been applied in aircraft construction due to their properties,” says Natalia Pushilina, scientific leader of the project. “Thus, BT6 is used to manufacture turbine parts subject to high temperatures, corrosive media, and saturation with atmospheric hydrogen during operation.”
The researchers say using three-dimensional (3-D) printing with additive manufacturing enables them to produce specific parts of any alloy configuration. In turn, this process consumes less material. “Our goal is to develop a technology for printing individual complex parts out of titanium,” explains engineer Viktor Kudiyarov.
The researchers are looking to reveal patterns between print parameters and the characteristics of manufactured items. By varying them, it is possible to obtain products with different specified properties. An essential part of the technology is creating a gradient structure at the surface layer.
“Our technology allows the production of parts with uniform thickness throughout and parts with a modified surface layer,” Kudiyarov says. “The modification of the upper layer will improve the properties. For example, it will make them more wear-resistant, more resistant to hydrogen.”
Such modifications require an extra production process. A homogeneous part is made first, and then an additional coating is applied. The technology enables these processes to be combined—details are printed immediately with a modified layer. The team is also studying technological modes and properties of the samples.
Source: TPU, tpu.ru/en.