Abstract: A spin valve magnetic head, providing on a substrate, a laminated structure that has an antiferromagnetic layer, fixation layer, non-magnetic layer and unconstraint layer, and having a first underlayer of Ta, a second underlayer of NiFeCr and a third underlayer of NiFe, which underlayers are interposed between the substrate and the laminated structure.

Abstract: A spin valve magnetic head which can offer high output and stable operation is proposed.

Abstract: A magnetic head with low non-linear transition shift, excellent recording capability at high-frequency bands and good reproduction efficiency is disclosed.A second metallic magnetic layer of an FeMN system (M : at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta and Cr) is formed on the surface facing the gap of the leading-side magnetic core of the magnetic head. On the surface facing the gap of the trailing-side magnetic core of the magnetic head provided is a first metallic magnetic layer of an FeMN system (M : at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta and Cr) having a higher saturation magnetic flux density than the second metallic magnetic layer. These two cores are butted against each other via a non-magnetic material and bonded with bonding glass.

Abstract: There is provided according to the present invention a magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:Fe.sub.100-x-y M.sub.x B.sub.y (atomic %)wherein M represents at least one element selected from Ti, Zr, Hf, V, Nb, Mo, Ta, Cr, W and Mn, 4.ltoreq.x.ltoreq.15, 2.ltoreq.y.ltoreq.25, and 7.ltoreq.x+y.ltoreq.35, at least 50% of the alloy structure being occupied by crystal grains having an average grain size of 500 .ANG. or less, and the crystal grains being based on a bcc structure. It may further contain X (Si, Ge, P, Ga, etc.) and/or T (Au, Co, Ni, etc.). This magnetic alloy has an excellent saturation magnetic flux density, permeability and heat resistance.

Abstract: A magnetic alloy with ultrafine crystal grains having a composition represented by the general formula:Co.sub.100.sub.-x-y-z-a-b Fe.sub.a M.sub.x B.sub.y X.sub.z T.sub.b (atomic %)wherein M represents at least one element selected from Ti, Zr, Hf, V, Nb, Mo, Ta, Cr, W and Mn, X represents at least one element selected from Si, Ge, P, Ga, Al and N, T represents at least one element selected from Cu, Ag, Au, platinum group elements, Ni, Sn, Be, Mg, Ca, Sr and Ba, 0<a.ltoreq.30, 2.ltoreq.x.ltoreq.15, 10.ltoreq.y.ltoreq.25, 0.ltoreq.z.ltoreq.10, 0<b.ltoreq.10, and 12<x+y+z+b.ltoreq.35. Such a magnetic alloy can be produced by producing an amorphous alloy having the above composition, and subjecting the resulting amorphous alloy to a heat treatment to cause crystallization, thereby providing the resulting alloy having a structure, at least 50% of which is occupied by crystal grains having an average grain size of 500 .ANG. or less.

Abstract: A flying-type composite magnetic head comprising a slider made of a non-magnetic ceramic and having side rails extending longitudinally on both lateral sides of the head; a slit extending longitudinally in one of the side rails; and a magnetic core. The magnetic core is constituted by a pair of core pieces bonded to each other with a first glass layer and fixed in the slit of the slider with a second glass layer on both sides of the magnetic core. The core pieces have flat opposing surfaces parallel to each other for defining a magnetic gap with at least one of the opposing surfaces formed with an Fe-Al-Si thin layer. The magnetic core is provided in its track surface with a notch for restricting a track width, the notch having a depth equal to or greater than the depth of the magnetic gap, and the remaining thickness of the first glass layer bonding the magnetic core pieces being equal to or greater than the thickness of the magnetic core.

Abstract: A magnetic head having at least one magnetic gap in its magnetic path, which comprises an Fe-base solf magnetic alloy layer in the magnetic path, at least 50% of the structure of said alloy layer consisting of fine crystalline particles having a body-centered cubic structure and an average particle size of 500 .ANG. or less.