繰返し面内純せん断負荷下での炭素鋼薄膜のき裂発生におよぼす微視組織の影響

抄録

Even if metal thin film is the same material, it does not know that different mechanical characteristics form a bulk material are shown, and general fatigue behavior showing a bulk material does not necessarily appear. The present condition is that research of the fatigue behavior in the repetition shear load of a metal thin film is not made compared with the thing of load direction axis and bending. From studies of thin films in the cyclic shear loading to date, a crack with a locally slip in S10C occurs. The cause such crack occurs, the strain in the ferrite by applying the cyclic shear loading occurs, pearlite is considered to crack been concentrated deformed part that is sandwiched between the perlite harder than ferrite because no deformation occurs. So, in this study we used S45C that is high perlite volume fraction and has many of ferrite sandwiched perlite, observed intergranular crack, transgranular crack, and crack with locally slip. As a result, we confirmed difference of crystal orientation near the crack and the crack initiated along slip plane and not reached back face. And we considered that crack was initiated by local concentration of deformation.