Recently, the research team led by Wang Shenggang from the Institute of Metal Research, Chinese Academy of Sciences, has made a significant breakthrough in the field of nanocrystalline 304 stainless steel sheets: for the first time, the mechanical properties and corrosion resistance of nanocrystalline 304 stainless steel sheets prepared through deep rolling technology have been simultaneously improved, clearing a key obstacle for the industrial application of bulk nanocrystalline metal materials.
Since the concept of nanomaterials was proposed in the 1980s, nanocrystalline powders and thin films have been widely used. However, the interaction between stress and corrosion has made it difficult to simultaneously improve the mechanical and corrosion resistance of nanocrystalline and ultrafine-grained metal structural materials during service, which has been a key factor hindering the industrialization of these materials. This team achieved nanocrystalline 304 stainless steel sheets without martensite and with uniform microstructure by controlling the total rolling deformation, deformation per pass, and rolling temperature, which became the key factor in reducing the negative impact of the interaction between stress and corrosion on mechanical and corrosion resistance and improving these properties. Compared with ordinary 304 stainless steel (TPC-304), the stainless steel sheets have improved high-temperature oxidation resistance, corrosion resistance, and strain fatigue resistance.
This breakthrough not only solves the problem of the difficulty in balancing mechanical and corrosion properties in traditional nanomaterials, but also provides a new research paradigm for materials science through its valence electron structure theory. This technology is ready for industrialization and is expected to promote the lightweight, long-life, and green development of downstream related equipment.
