A low-temperature-resistant and high-strength stainless-steel jacket is a key component in the superconducting magnet of a fusion reactor. The development of cryogenic structural materials with high strength and toughness poses a challenge for the future development of high-field superconducting magnets in fusion reactors. The yield strength of the International Thermonuclear Experimental Reactor developed for low-temperature structural materials at \({4.2}\,{\textrm{K}}\) is below \({1100}\,{\textrm{MPa}}\) , which fails to meet the demand for structural components with yield strengths exceeding \({1500}\,{\textrm{MPa}}\) at \({4.2}\,{\textrm{K}}\) in the future fusion reactors. CHSN01 (formerly N50H), which is a low-temperature structural material developed in China, exhibits exceptional strength and toughness, thereby making it highly promising for practical applications. Recently, a \({30}\,{\textrm{t}}\) jacket measuring approximately \({5000}\,{\textrm{m}}\) in total length was produced. Its low-temperature mechanical properties were tested using a sampling method to ensure compliance with application requirements. This paper presents the experimental data of the CHSN01 jacket and tests of the physical properties of the material in the temperature range of 4–300 K. The physical properties were unaffected by magnetic field. Furthermore, this paper discusses the feasibility of employing CHSN01 as a cryogenic structural material capable of withstanding high magnetic fields in next-generation fusion reactors.
