Title :
Corrosion study in TbFeCoCr amorphous magneto-optical films
Author :
Kobayashi, H. ; Ogino, K. ; Takayama, S.
Author_Institution :
IBM Japan, Kanagawa, Japan
fDate :
9/1/1990 12:00:00 AM
Abstract :
(Tb20Fe65Co15)94Cr 6 film shows high corrosion resistance with good magnetooptical properties, Hc=4.9 kOe, θk=0.3°, Ku=1.4×106 erg/cm3 and Tc=230°C. Pit corrosion in 1N-NaCl aqueous solution and wet corrosion in 85°C and 85%RH atmosphere were studied for TbFeCo films with and without Cr addition. It is suggested that pit corrosion occurs by a chemical reaction between the anodic pit wall and the cathodic film surface, resulting in a piling up of corroded products inside the pits. On the other hand, wet corrosion in TbFeCo and TbFeCoCr films shows a bubble-chain-like morphology similar to conventional filiform corrosion observed in a coated film. This seems to take place by discontinuous movement of the anodic reaction area ahead of the bubbles
Keywords :
chromium alloys; cobalt alloys; corrosion; ferromagnetic properties of substances; iron alloys; magnetic properties of amorphous substances; magnetic thin films; magneto-optical effects; terbium alloys; (Tb20Fe65Co15)94Cr 6; 230 degC; 85 degC; NaCl; TbFeCo films; TbFeCoCr; amorphous magneto-optical films; anodic pit wall; bubble-chain-like morphology; cathodic film surface; chemical reaction; corroded products; filiform corrosion; high corrosion resistance; magnetooptical properties; pit corrosion; wet corrosion; Amorphous magnetic materials; Amorphous materials; Atmosphere; Chromium; Corrosion; Magnetic anisotropy; Magnetic films; Magnetic properties; Perpendicular magnetic anisotropy; Plasma measurements;
Journal_Title :
Magnetics, IEEE Transactions on
