INSIDE CHSN01: CHINA'S HIGH-STRENGTH STEEL POWERING NEXT-GEN FUSION REACTORS

Summary from the TLDR newsletter

Fusion projects such as the International Thermonuclear Experimental Reactor (ITER) rely on 316LN or JK2LB cryogenic stainless steels, which hold up well at liquid-helium temperatures, but their yield strength limits the magnetic field of ITER at 11.8 tesla and forces a large, expensive machine design. Chinese developers created CHSN01 (China High-Strength, Low-Temperature Steel No. 1) to withstand 20 Tesla fields and 1.3 GPa combined electromagnetic stress while still stretching about 30% before breaking. It keeps those properties after 60,000 on/off cycles, the lifetime workload of China's Burning-Plasma Experimental Superconducting Tokamak (BEST). CHSN01 can be used in MRI scanners, particle accelerators, maglev trains, and even quantum-computing dilution refrigerators - swapping in a stronger and tougher steel could shrink magnet footprints and extend service intervals across the board.