Alloy composition, Fe-based nano-crystalline alloy and forming method of the same
AssigneesNEC Tokin Corporation, Tohoku University
InventorsAkiri Urata, Yasunobu Yamada, Hiroyuki Matsumoto, Shigeyoshi Yoshida, Akihiro Makino
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Abstract
An alloy composition of Fe(100-X-Y-Z)BXPYCuz, where 4≦X≦14 atomic %, 0<Y≦10 atomic %, and 0.5≦Z≦2 atomic %. This alloy composition has an amorphous phase as a main phase. This alloy composition is used as a starting material and exposed to a heat-treatment so that nanocrystals comprising no more than 25 nm of bccFe can be crystallized. Thus, an Fe-based nano-crystalline alloy having superior magnetic properties can be obtained.
Claims10
An Fe-based nanocrystalline alloy formed from an alloy composition of the formula Fe(100-X-Y-Z)BXPYCuz having an amorphous phase as a main phase, wherein 79≦100-X-Y-Z≦86 atomic %, 4≦X≦9 atomic %, 1≦Y≦10 atomic %, and 0.5≦Z<1.2 atomic %,
- wherein the alloy composition has a first crystallization start temperature (Tx1) and a second crystallization start temperature (Tx2) which have a difference (ΔT=Tx2−Tx1) of 70 to 200° C.,
- wherein the Fe-based nanocrystalline alloy is formed by heating the alloy composition to a temperature in a range of Tx1 −50° C. to Tx2 −77° C.,
- wherein nanocrystals of the Fe-based nanocrystalline alloy have an average diameter of 5 to 25 nm existing in the amorphous phase, and
- wherein the Fe-based nano-crystalline alloy has coercivity of 20 A/m or less and a saturation magnetic flux density of 1.6 T or more.
Dependencies are inferred from the claim text.