| Title |
Research papers / Mechanical Behaviors : Effects of Tic and Cr23C6 Carbides at Grain Boundaries on the Creep - Fatigue Interaction Behaviors in AISI 321 Stainless Steel |
| Authors |
민경선(Kyung Seon Min),남수우(Soo Woo Nam),이수찬(Soo Chan Lee) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
In order to investigate the effects of TiC and Cr_23C_6 carbides on the creep-fatigue behaviors, total strain range controlled creep-fatigue tests were conducted at 600℃ in the TiC and Cr_23C_6 aged AISI 321 stainless steels with various carbide densities at grain boundary. It is observed that creep-fatigue lives of small TiC and TiC aged alloys are longer than that of Cr_23C_6 aged alloy in the same test conditions. To verify differences of creep-fatigue life between TiC and Cr_23C_6 aged alloys, microstructural observations are conducted by scanning electron microscope(SEM) and transmission electron microscope(TEM). It is expected that cavitation resistance of TiC aged alloy is stronger than that of Cr_23C_6 aged alloy. From the microstructural observations, it is verified that formation and growth of grain boundary cavities in TiC carbides are more retarded than in Cr_23C_6 carbides. Therefore, it is suggested that the types of carbides are a more prominent factor than the density of carbides for grain boundary cavitation in austenitic stainless steels. |