China Achieves Mass Production of Key Fusion Component, CHSN01 Jacket
China has successfully mass-produced a 30-ton, 5-km-long cryogenic jacket using its domestically developed CHSN01 material. This advanced steel exhibits exceptional mechanical properties at 4.2 K, making it an ideal core component for Cable-in-Conduit Conductors (CICC) in future fusion reactors. The achievement not only meets stringent demands for next-generation fusion energy but also demonstrates great potential for other cutting-edge applications.
Exceptional Jacket Performance: A New Benchmark in Cryogenic steel
Testing at 4.2 K validates the outstanding properties of the CHSN01 jacket, achieving an average yield strength of 1560 MPa, elongation of 32.7%, and fracture toughness of 220 MPa·m ¹/² . Notably, CHSN01 delivers a 40% higher yield strength than the widely used 316LN steel while matching its plasticity and toughness, and demonstrates superior fatigue resistance.
An Enabling Material for Extreme Environments
CHSN01’s non-magnetic, high-strength, and high-toughness properties under 20 K make it a versatile key material. It is not only critical for next-generation fusion magnets but also promises significant weight savings in advanced cryogenic applications—from spaceflight fuel tanks to hydrogen energy infrastructure—potentially replacing 316LN where extreme performance is required.
the complete study is accessible by via DOI: 10.1007/s41365-025-01847-5
Nuclear Science and Techniques
Experimental study
Not applicable
Mass production and performance evaluation of CHSN01 jacket for future fusion applications
4-Jan-2026