Rhenium doped chromium–alumina composites for high-temperature applications

• Development of novel chromium–alumina composite materials with rhenium addition
• The obtained materials have high relative density and good mechanical properties.
• Re during sintering dissolves in Cr and forms Cr–Re solid solution as a new matrix.
• Good agreement between model and experiment for residual stresses and Young's modulus.
• Cr/Re/Al2O3 composites may be interesting for energy and transport applications.

Dense chromium–alumina composites doped with rhenium have been developed by the hot pressing method (bulk composite) and plasma spraying (composite coating). The obtained materials show superior mechanical properties, insensitivity to chemically aggressive environment, good resistance to frictional wear and oxidation at elevated temperature. These enhanced properties make the Cr/Re/Al2O3 composites interesting structural materials for energy and transport applications operating in demanding service conditions, e.g. fluidal boilers in power plants or valve seats in combustion engines.