Nano Extreme Temperature (NeXT) Steel: Balancing Thermal Properties, Oxidation Resistance and Extreme High Temperature Strength for Advanced Energy & Manufacturing Applications
Category: Mechanical/Materials
Developers: Oak Ridge National Laboratory; Cummins, Inc.
Product Description:Nano eXtreme Temperature (NeXT) steel is a new medium-carbon martensitic steel that combines chemistry and thermal processing to achieve a 46% increase in 600°C fatigue strength at 20% less cost than H-series steels while maintaining oxidation resistance. First application is advanced pistons, enabling higher-efficiency heavy-duty freight vehicle engines. ORNL and Cummins, Inc. have developed and rigorously tested, at both laboratory and engine test scales, the new NeXT steel, a medium-carbon, 3 wt % chromium steel with a combination of mechanical and thermal performance advantages at 75°–100°C higher temperature than other steels in this class. The alloy’s martensitic structure is designed to form nanoscale, intra-lath strengthening carbides that provide stable mechanical properties to above 600°C. The alloying strategy provides oxidation resistance to 600°C while maintaining necessary thermal properties. NeXT offers fatigue performance up to 600°C. NeXT steel has been successfully engine-tested and is available as high-performance piston crowns for HD engines. The alloy can be tempered to intermediate strengths while maintaining key properties, creating opportunities for pistons for a wide range of HD vehicles from class 2b to 8. The combination of superior high-temperature mechanical performance, thermal properties, environmental resistance and manufacturability of NeXT steel could open a field of new opportunities for affordable, advanced product design across a range of industries, including freight, tooling, automotive, industrial, energy and defense.
Developers: Oak Ridge National Laboratory; Cummins, Inc.
Product Description:Nano eXtreme Temperature (NeXT) steel is a new medium-carbon martensitic steel that combines chemistry and thermal processing to achieve a 46% increase in 600°C fatigue strength at 20% less cost than H-series steels while maintaining oxidation resistance. First application is advanced pistons, enabling higher-efficiency heavy-duty freight vehicle engines. ORNL and Cummins, Inc. have developed and rigorously tested, at both laboratory and engine test scales, the new NeXT steel, a medium-carbon, 3 wt % chromium steel with a combination of mechanical and thermal performance advantages at 75°–100°C higher temperature than other steels in this class. The alloy’s martensitic structure is designed to form nanoscale, intra-lath strengthening carbides that provide stable mechanical properties to above 600°C. The alloying strategy provides oxidation resistance to 600°C while maintaining necessary thermal properties. NeXT offers fatigue performance up to 600°C. NeXT steel has been successfully engine-tested and is available as high-performance piston crowns for HD engines. The alloy can be tempered to intermediate strengths while maintaining key properties, creating opportunities for pistons for a wide range of HD vehicles from class 2b to 8. The combination of superior high-temperature mechanical performance, thermal properties, environmental resistance and manufacturability of NeXT steel could open a field of new opportunities for affordable, advanced product design across a range of industries, including freight, tooling, automotive, industrial, energy and defense.
