Amorphous metal thin strip, laminated core, and amorphous metal thin ribbon punching method
A punching method with a favorable punchability with respect to amorphous metal thin ribbons, an amorphous metal thin strip produced by the method, and a laminated core, are provided. The amorphous metal thin strip has a thickness of from more than 30 μm to 50 μm, and a side configured by a punched surface on which at least a shear droop, a shearing surface, and a fractured surface are observed, the width of the shear droop relative to the thickness of the metal thin strip being 30% or less at the side.
1. An amorphous metal thin strip, having an alloy composition represented by the following formula:
Fe 100-a-b-c-d B a Si b C c M d
wherein, in the formula, M is at least one of Al, Sn, Cr, Mn, Ni or Cu, and a, b, c, and d satisfy 7≤a≤20, 1≤b≤19, 0≤c≤4, and 0≤d≤2 in atomic %,
comprising:
a side configured by a punched surface on which at least a shear droop, a shearing surface, and a fractured surface are observed, wherein:
the metal thin strip has a thickness of 30.3 μm or larger and 50 μm or smaller, and
at the side, a width of the shear droop relative to the thickness of the metal thin strip is 30% or less.
2. The amorphous metal thin strip according to claim 1 , wherein the width of the shear droop is 8 μm or less.
3. The amorphous metal thin strip according to claim 1 , satisfying the relationship: 0.03≤d≤2.
4. A laminated core in which a plurality of the amorphous metal thin strips according to claim 1 are disposed one on another in layers.
5. The laminated core according to claim 4 , satisfying the relationship: 0.03≤d≤2.
6. An amorphous metal thin ribbon punching method, comprising:
preparing an amorphous metal thin ribbon with a thickness of 30.3 μm or larger and 50 μm or smaller;
punching the amorphous metal thin ribbon; and
forming a side of the amorphous metal thin ribbon configured by a punched surface on which at least a shear droop, a shearing surface, and a fractured surface are observed,
wherein, at the side, a width of the shear droop relative to the thickness of the metal thin strip is 30% or less,
wherein the amorphous metal thin ribbon has an alloy composition represented by the following formula:
Fe 100-a-b-c-d B a Si b C c M d
wherein, in the formula, M is at least one of Al, Sn, Cr, Mn, Ni or Cu, and a, b, c, and d satisfy 7≤a≤20, 1≤b≤19, 0≤c≤4, and 0≤d≤2 in atomic %.
7. The amorphous metal thin ribbon punching method according to claim 6 , wherein, in the formula, 0.03≤d≤2.
8. The amorphous metal thin ribbon punching method according to claim 6 , further comprising using a punching die configured by a punch and a die.
9. The amorphous metal thin ribbon punching method according to claim 8 , satisfying the relationship: 0.03≤d≤2.