metalenceramieke

Metalenceramieke is a category of materials that combines metallic and ceramic components to leverage the toughness of metals and the hardness and temperature stability of ceramics. The term covers metal-ceramic composites, often referred to as cermets, as well as ceramic matrices reinforced by metallic phases. In these materials, a ceramic phase provides high hardness, wear resistance and chemical stability, while an embedded metallic phase improves toughness, ductility and energy absorption, reducing brittleness compared with monolithic ceramics.

Common systems include WC-Co cermets (tungsten carbide particles in a cobalt binder), Al2O3- or SiC-based ceramics with metallic binders, and functionally graded metal-ceramic hybrids. The choice of phases and their proportions determine properties such as hardness, strength, fracture toughness and thermal conductivity.

Fabrication and processing typically rely on powder metallurgy, pressing and sintering, hot isostatic pressing, and diffusion bonding; increasingly, additive manufacturing methods are used to build complex shapes. Interfacial bonding between metal and ceramic, as well as thermal expansion mismatch, are important factors that influence performance and reliability.

Properties and limitations: metal content raises fracture toughness and impact resistance but thermal expansion mismatch, residual stresses, and interfacial bonding can affect performance; processing costs are a consideration. Durability in high-temperature and corrosive environments is also a key concern.

Applications include cutting tools and wear parts in machining, aerospace components, and dental restorations such as porcelain-fused-to-metal crowns. Ongoing research aims to optimize interfaces, develop graded materials, and explore new combinations of metal and ceramic phases.