Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : December 22, 2018 - December 24, 2018
Magnesium (Mg) would being attracted as biomaterial in the stent application since Mg had have to be biocompatibility and adjustment in body even though it has the disadvantage properties of low corrosion resistance and strength. For the improvement of the surface morphology we had tried to deposit pure Mg by a resistance heating deposition in vacuum on Mg 99.9wt% ribbon. Some of the specimens were deposited with the thickness of Mg as 1 μm in the deposition. All specimens were immersed in 0.9%NaCl at 37℃ for 0, 48 and 120 hours and then carried out tensile test and we’ve got the stress-strain relationship. Several areas in the specimens had been inspected the surface roughness with an atomic force microscope. It resulted that tensile strength (TS) of Deposited ones was higher than that of As-received. The difference of TS between the As-received and deposited ones were 36 MPa for 48 hours’ immersion and 11 MPa for 120 hours’. Yang’s module of the specimens immersed for 120 hours was lower than those of immersed for 0, 48 hours. The fracture of the specimens immersed for 48 hours is in ductile with crack propagation from the inside but the fracture immersed for 120 hours is from the surface to edge. Since average surface roughness of deposited ones was smaller than that of As-received, it shows that the surface quality of As-received ones is improved with depositing Mg. Nevertheless, the relationship between surface quality and strength in corrosion could not be clarified because the adhesion at the interface of deposition was insufficient due to less activation of the Mg ribbon’s surface. It might be important for this research to reconsider surface preparation before depositing Mg.
