Scanning Cyclic Pressを用いたマグネシウム合金の表面改質に及ぼす負荷繰返し数の影響

抄録

A new surface modification technique, scanning cyclic press (SCP), was developed. SCP scans a metal surface with a vibrating indenter and refines the surface layer using cyclic compressive loading. This study applied SCP to the surface of magnesium alloy AZ31 under number of cyclic loading of 3.2×10⁵ and 8.0×10⁶ cycles to investigate the effect on surface structure. After applying SCP, the cross sections of specimens were observed by electron back scattering diffraction (EBSD) using SEM. As a result, a fine structure around 1－10 μm in grain size and a twin were formed in the surface layer of both specimens. The depth of these structures from the surface remained unchanged regardless of the number of cyclic loading. However, the surface structure under 8.0×10⁶ cycles was finer than that under 3.2×10⁵ cycles. This is likely caused by the increase of accumulated plastic strain during SCP process.