Scientists have discovered which additive enhances the properties of aluminum alloys.

Aluminum alloys are widely used in the automotive and aerospace industries due to their lightweight nature and availability. Alloys based on aluminum with the addition of silicon and magnesium are well-suited for 3D printing, as they exhibit high fluidity, corrosion resistance, and mechanical stability even at elevated temperatures.

“Despite the many advantages of aluminum alloys, components made from this material possess relatively low hardness and wear resistance. To enhance these characteristics, various surface treatment methods are employed, such as laser cladding, anodizing, and thermal spraying. However, high-temperature techniques can lead to changes in the material's chemical composition, the development of residual stresses, and microcracks. A more modern approach is cold spraying, which allows for coatings to be applied without heating to high temperatures,” explained Veronica Suvorova, a candidate of technical sciences and research associate at the Center for Structural Ceramic Materials at NITU MISIS.

For the cold spraying method, powder mixtures are created with the addition of reinforcing components, such as ceramic particles like zirconium nitride. The main objectives are to minimize particle losses during the spraying process and to determine the optimal additive content needed to achieve the best results.

Scientists at NITU MISIS have developed powders with composite particles and studied the effect of the quantity and distribution of zirconium nitride particles on the structure, hardness, stiffness, and wear resistance of composite coatings. Powders with 10 percent of the additive proved ineffective, even worsening the adhesion between layers and reducing the hardness and wear resistance of the materials. In powders containing 30 percent zirconium nitride, the particles were evenly distributed within the alloy matrix, allowing for the creation of dense coatings and reducing the loss of ceramic particles during spraying from 50 to two percent.

“The application of composite coatings with 30 percent zirconium nitride demonstrated the best results. The strength, hardness, elastic modulus, and wear resistance of the substrate (aluminum alloy) significantly increased, which is particularly promising for use in the automotive and aerospace industries, where lightweight materials with excellent mechanical properties are required,” added Dmitry Moskovskikh, a candidate of technical sciences and director of the Center for Structural Ceramic Nanomaterials.

The results of the research, published in the scientific journal Advanced Engineering Materials (Q1), contribute to the development of hybrid additive manufacturing technologies that combine 3D printing and cold spraying.