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About Novel Ceramic/Metallic Materials

Novel ceramic and metallic materials offer many advantages over other materials in a variety of structural applications—particularly in the defense, transportation, energy, electronics, and process industries. This Technology Map covers a range of advanced ceramic and metallic materials, notably advanced structural ceramics, ceramic-matrix composites, metal-/intermetallic-matrix composites, and interpenetrating-phase composites. Although key differences exist, these materials overlap significantly in terms of processing technologies, materials properties, and applications. In general, the high strength, wear resistance, and low weight of these materials can contribute to increasingly efficient and resilient transportation and power-generation systems. In addition, the thermal and electrical properties of these materials offer users advantages in many applications. However, performance, processing, and cost issues continue to limit the commercial viability of these advanced monolithic and composite materials. Processing difficulties and toughness issues resulting in poor reliability meant that structural-ceramic materials failed to live up to the initial promise of the 1980s. In addition, IMCs failed to live up to the initial hopes of researchers in the 1990s. Developments in areas as diverse as advanced property databases, computer modeling of materials, industry familiarity, and industry structures will all aid commercialization of such advanced materials.

Recent years have seen a reevaluation of ceramic materials, with a significant shift in opinion about the realistic market size and technical benefits of these materials. Structural ceramics are already established in applications—for example, wear components and filters—in which engineers can design around these materials' intrinsic limitations. The ceramics industry has already experienced significant consolidation. Further technical advances are still highly possible, leading to tougher, more cost-effective, and more reliable ceramics that will increase the range of applications for these materials.

Following their initial development in the 1960s and 1970s, high-performance MMCs first found use in various high-tech aerospace and defense applications. The use of exotic MMCs in these applications continues. In addition, industry researchers have worked to optimize the properties of lower-cost MMCs—especially AMCs—for volume use in, for example, automotive parts and electronic packaging/components. Significant commercialization has already occurred in these applications. Materials science represents a set of interlinked, constantly evolving, and maturing technologies. Developments in materials technologies promise new ceramic and metal-ceramic composite materials that overcome existing limitations. Many industries are also driving the development of new materials that perform both structural and functional roles. Novel ceramic and metallic materials remain important and promising candidates for many applications.