Ceramic matrix composites are gaining a foothold for some high-performance applications. So what are they, how are they made and what’s the potential for CMCs?
Within the high-performance composites market, ceramic matrix composites (CMCs) are garnering a lot of attention. CMCs combine a ceramic fiber embedded in a ceramic matrix to produce a finished CMC part. They are sought after for applications with demanding thermostructural requirements.
While your company may focus on more traditional CFRP and GFRP applications, it’s still important to understand and keep an eye on ceramic matrix composites. According to the Freedonia Group, an industry research firm, demand for advanced ceramics in the United States will increase 5.1 percent annually to $13.6 billion in 2017.
Applications for CMCs
Ceramic matrix composites are key enabling technologies for efficient gas turbines for aerospace and maritime propulsion as well as land-based electric power generation, hypersonic, nuclear power and industrial processing applications. The technology for manufacturing CMCs is maturing to the point where domestic and international companies, as well as the federal government, are making large investments to scale up production in the United States and abroad.
Demand for CMCs for commercial aerospace gas turbine engines is one of the principal drivers for these investments. CMCs have the potential to enable a step change in the fuel efficiency of gas turbine engines. In general, the hotter the engine runs, the better the fuel efficiency. Increases in engine temperature capability have historically been enabled by advances in metal technologies and through thermal barrier coatings. Those advances are rapidly approaching their theoretical limits. CMCs have emerged as the material of choice for many future engines, in large part because their operating temperatures are around 1300 C.
Industry leaders have announced significant investments – construction of new manufacturing facilities, expanded employment and capital equipment purchases – to transition CMCs into commercial gas turbine engines. For example, General Electric is adding jobs at a retooled facility in North Carolina to produce CMC components for its new LEAP gas turbine engine. The company currently has orders for more than 6,000 units. Rolls Royce and Boeing/ATK-COIC anticipate similar investments in the U.S. to produce CMC components for gas turbine engines. These companies consider CMCs critical to meeting demand for greater fuel efficiency in aviation propulsion.