Modifier could strengthen aluminum parts

The National University of Science and Technology (NUST MISIS) in Moscow, Russia, has developed modifiers designed to strengthen 3D printed aluminum-matrix composites parts for aerospace.

The scientists from the non-ferrous metals and gold department have proposed a technology that can double the strength of aluminum-matrix composites obtained by 3D printing from aluminum powders and aluminum-based alloys , while bring them up closer to the quality of titanium alloys.

Titanium’s strength is about at the factor of six times higher than that of aluminum, but the density of titanium is also 1.7 times higher, the researchers says. While titanium is the optimal metal for manufacturing products manufacturing for the aerospace industry nowadays, it carries the risk of fire and explosion as a powder. One should be very careful by titanium powders 3D sintering.  Aluminum is lightweight, with a density of 2700 kg/m3 and moldable, with an elasticity modulus of ~70 MPa but alone pure aluminum is not strong or hardsolid enough.

The solution on how to strengthen aluminum 3D printing was proposed by the research team led by Professor Alexander Gromov from the NUST MISIS, Department for Non-Ferrous Metals and Gold.

‘We have developed a technology to strengthen the aluminum-matrix composites obtained by 3D printing (SLM method), and we have obtained innovative precursors - modifiers by burning aluminum powders burning,’ said Alexander Gromov, head of the research group. ‘Combustion products — aluminum nitrides and aluminum oxides — are specifically prepared for 3D sintering: branched surfaces with transition nanolayers are formed between the particles. It is the special properties and structure of the precursor’s surface that allows the particles to be firmly attached to the aluminum matrix and, as a result, [doubles] the strength of the obtained composites.’

The developed modifying-precursors, based on aluminum nitrides and aluminum oxides and obtained through combustion, have become the basis of the new composite and can be used in products for the aerospace industry. Currently, the team of developers is testing the prototypes obtained with the help of new technology.

The research results have been published in the scientific journal Sustainable Materials and Technologies.

This story is reprinted from material from NUST MISISwith editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.