The Company started preliminary study on critical materials of 700℃ ultra-supercritical coal-fired units in 2008, and since then has carried out basic experimental research on 6 key nickel-base alloys defined in the Europe and USA 700℃ Plan including Alloys 740, 263, 617, 625, and 718. The research covers microstructure and mechanical property, high-temperature aging for 10000 hours, and structure stability. Full study has been made on the research, development, and production capabilities of China in high-temperature alloys, and the necessity and feasibility for implementing 700℃ power projects in China have been demonstrated and evaluated. In 2011, 1000h high-temperature steam oxidation tests were carried out for the above-mentioned alloys.
In June 2010, the National Energy Administration established the National Innovation Alliance for 700℃ Ultra-supercritical Coal-fired Power Technology. China Huaneng Group acts as vice chairman of the Alliance, and undertakes the 700℃ ultra-supercritical coal-fired power technology project of the National Energy Administration.