SUS304ステンレス鋼の粒界腐食防止のための加工熱処理

抄録

Simple and practical countermeasures to intergranular corrosion of normal commercial heats of SUS 304 stainless steels were developed by utilizing the microstructural features of the material aged after plastic deformation without modifying alloy composition. In this method, manufacturing process was modified through full solution treatment and subsequent cold working and aging at carbide precipitation temperature and then heating to recrystallization at temperatures of the levels low enough so that no carbide redissolution takes place.
In contrast to the traditional mill annealing process, the thermomechanically treated material showed satisfactory immunity to intergranular corrosion. A typical structure obtained by this process is associated with fine crystal grain size and evenly dispersed fine spherical M₂₃C₆ type carbide particles.
In addition to such resistance the material showed improved tensile properties due to the Hall-Petch effect with the refined grain size and the fine carbide dispersion.