| 摘要 |
PURPOSE:To make equal the coeffs. of thermal expansion of a nonmagnetic base and thin magnetic film and to obviate the exfoliation of the thin magnetic film and the deterioration of the magnetic characteristic in a magnetic head combined and united with the nonmagnetic base and thin magnetic film by consisting the nonmagnetic base of a specific ceramic compsn. CONSTITUTION:The Na2O-Ta2O5 ceramic compsn. is used as the nonmagnetic substrate. The Na2O-Ta2O5 ceramic compsn. has the compsn. expressed by the generation formula xNa2O.yTa2O5 and the compsn. range thereof is set at 0.85<=x/y<=1.00. The coefft. of linear expansion alpha is <130X10<-7>/ deg.C which is too small as compared to the thin magnetic film is x/y is <0.85. Sintering is defective and the ceramic compsn. having good quality is not obtainable when x/y exceeds 1.00. The coefft. of linear expansion alpha of the ceramic compsn. is controlled to 130-170X10<-7>/ deg.C when x/y is set at 0.85<=x/y<=1.00. A small amt. of additive may be added to the ceramic compsn. in order to improve the sinterability thereof. Such additive is exemplified by Li2O, etc. for substituting Na with a small amt. of the other alkali metal and Nb2O5, etc. for substituting Ta. |
