Ceramic matrix composites (CMCs) are a breakthrough materials technology for jet engines that started at our Global Research Center in Niskayuna and jointly developed with our Aviation business. CMCs will replace certain metal components in the hot section of the engine.
What’s so innovative about CMCs is that they can be made as strong as metal, yet are much lighter and can withstand much higher temperatures. These advantages will help us lower fuel burn and emissions, while increasing the efficiency of future GE aircraft engine platforms.
GE’s CMCs can operate at temperatures exceeding the capability of current nickel alloys typically used in high-pressure turbines. Today’s metal parts require extensive dedicated cooling air. This directly takes away from the primary engine airflow and reduces efficiency. CMCs can operate with little or no cooling, providing a significant efficiency boost to the cycle. CMCs also are one-third the weight of nickel.
For more than a half century, GE has been at the forefront of developing advanced materials for turbine applications. The invention of the Rene-family of nickel-based superalloys led to continuous improvement in temperature capability from the 1960s to the 1990s. Thermal barrier coatings and internal cooling was able to deliver incremental improvements as well.
With more than 20 years of experience, GE has taken CMCs from the lab to robust, cost-effective manufacturing. GE Aviation already has a CMC manufacturing facility in Newark, Delaware, and more recently announced plans to build an advanced composite component factory near Asheville, North Carolina, to produce CMC components. CMCs deliver a truly revolutionary leap in temperature capability beyond any advanced metal alloy. (See chart.)
CMC durability has been validated through significant testing in customer gas turbine engines accumulating almost 30,000 hours of operation. CMCs will play a key role in the performance of CFM’s LEAP turbofan engine (pictured). Entry into service begins in 2016 for the Airbus A320neo and 2017 for the Boeing 737max.