Researchers at NUST MISIS have created a new aluminum alloy with the addition of calcium and titanium, which combines high heat resistance, wear resistance, and ductility.
Widely used aluminum-silicon alloys have good casting properties and low cost, but they do not withstand shock loads and complex deformations well due to their low ductility. The proposed alternative based on the aluminum-calcium system with the addition of titanium is free from this disadvantage.
The key feature of the new material is the structure of a "natural composite" that forms during the solidification of the alloy. The smallest solid particles are evenly distributed in a ductile aluminum base, based on the principle of reinforced material. Hardness naturally increases with an increase in the proportion of calcium, and alloys with a titanium content of 0.5% showed the optimal combination of properties: with this composition, large primary crystals of the Al₃Ti phase are practically absent, instead a compact Al₂₀CaTi₂ phase with a size of no more than 4 μm is formed.
The material has high casting properties and exceptional deformation ductility. In the future, it can be used to create lightweight and durable parts for mechanical engineering, primarily for motor vehicles.
The results are published in the journal Materials Letters, and the work was supported by a grant from the Russian Science Foundation.
