Scientists from NUST MISIS have developed a nanocarbon additive to aluminium powder which they say increases the hardness of 3D printed products by 1.5 times. The additive is obtained from the waste products when processing petroleum gas.

The main field of application for aluminium 3D printing is the creation of high-tech parts for the aviation and space industries. The presence of even the slightest defects in printed structures is critical to the safety of the technology being created. According to NUST MISIS scientists, the main risk of such defects is the high porosity of the material, caused, among other reasons, by the qualities of the original aluminium powder. To ensure a uniform and dense microstructure of printed products, scientists from the MISIS Catalis Lab proposed adding carbon nanofibres to the aluminium powder. The use of this modifying additive makes it possible to ensure low porosity.

"Changing the chemical and phase composition of the powder for printing by introducing additional components into the main matrix allows improving its properties. In particular, carbon nanofibres have high thermal conductivity, which helps to minimise temperature gradients between printed layers during product synthesis, at the stage of selective laser melting. Thanks to this, the microstructure of the material can be almost completely eliminated from inhomogeneities," says the head of the laboratory, professor at NUST MISIS, Ph.D. Alexander Gromov.

The technology for the synthesis of nanocarbon additives developed by the research team includes methods of chemical deposition, ultrasonic treatment, and IR heat treatment. During its catalytic decomposition, carbon accumulates in the form of nanofibres on dispersed metal particles of the catalyst. Usually, associated gases are simply burned in the fields, which harms the environment. Therefore, the application of the new method also has a serious environmental significance, adds Professor Gromov. The study has been carried out jointly with specialists from the Boreskov Institute of Catalysis SB RAS. In the future, the research team plans to determine the optimal conditions for selective laser melting of new composite powders, as well as to develop a technology for post-processing and industrial use of synthesised products.