The Korea Institute of Materials Science (KIMS, President Lee Jeong-hwan), a government-funded research institute under the Ministry of Science and ICT, is expected to domestically produce core titanium (Ti) components for power generation turbines, which previously relied on strategic imports, leading to domestic titanium technology independence.

The Korea Materials Research Institute announced on the 4th that the research team led by Dr. Lee Sang-won of the Titanium Research Lab of the Metal Materials Research Headquarters succeeded in localizing the manufacturing technology for titanium compressor blades, a key component of next-generation composite gas turbines, through joint research among industry, academia, and research institutes including Hansco, Pusan National University, S&B, and Jinyoung TBX.

Titanium compressor blades can inhale and compress atmospheric air in a wide flow path, and can efficiently supply high-temperature/high-pressure air to the combustor in terms of aerodynamic performance compared to existing steel materials, making them a key component for achieving high energy efficiency in next-generation combined gas turbines.

Replacing existing compressor blades with steel or titanium is expected to increase energy efficiency by about 0.1%.

This figure represents an economic value of several million dollars per year per gas turbine. For this reason, titanium compressor blades are being used in the world's most energy-efficient overseas gas turbine models that have been recently developed.

This technology is for manufacturing large 28-inch compressor blades using high-strength titanium alloy (Ti-6Al-4V). It is significant that the entire process (melting → intermediate materials → die forging → processing) from materials to parts manufacturing has been manufactured using pure technology, thereby achieving technological independence and establishing a manufacturing value chain domestically.

The research team conducted vacuum melting analysis and processing heat treatment process design to enable manufacturing using only domestic infrastructure across the entire process from materials to components, and supported securing the reliability of domestically produced titanium blades through mechanical/chemical evaluations of each process product.

In particular, by connecting the value chain of each manufacturing process domestically, the competitiveness of domestic products was enhanced through improvements in price, delivery time, and quality.

Recently, there has been an increasing demand for improved energy efficiency of combined gas turbines due to carbon dioxide (CO2) emission regulations and a reduction in domestic energy import dependence.

In addition to increasing the combustion temperature and pressure of gas turbines, it is essential to enlarge the turbine blades to achieve this.

Existing heat-resistant steel materials are being replaced with titanium alloys, which are high-strength, lightweight metal materials, due to the increased weight caused by larger parts, which increases the possibility of parts breaking during rotation. However, even these are being imported entirely from overseas due to the lack of domestic technology and related infrastructure.

Our country has developed the world's fifth independent gas turbine model and is currently developing a combined gas turbine with an energy efficiency of 63%. The government has also announced a strategy to achieve the goal of becoming one of the top four global gas turbine manufacturers by 2030. The developed product is in line with the direction of domestic gas turbine power generation and is expected to contribute to the development of world-class domestic gas turbines.

Senior Researcher Lee Sang-won of the Materials Research Institute, who is in charge of the research, said, “The enlargement of gas turbine blades using titanium is an essential technology for the development of eco-friendly composite gas turbines.” He added, “This technology can also be quickly applied to the domestic production of large titanium parts for defense, aerospace, and military applications, which have been difficult to develop so far, so its ripple effects are expected to be large.”

This research was carried out with the support of the Ministry of Trade, Industry and Energy's Materials and Components Technology Development Project (Development of Manufacturing Technology for 1,250 MPa-Class High-Strength Titanium Alloy Large Blades).

Currently, Doosan Energy Co., Ltd., the demand company, has purchased a large number of domestically produced titanium blades and is conducting reliability evaluations for commercialization, and is reviewing application to the next-generation domestically produced gas turbine model.

In addition, the research team is working to advance the mass production period of titanium blades by conducting additional research on process improvement to enhance the product's price, quality, and delivery competitiveness.