Material having a high elastic deformation and process for producing the same

Abstract

A Co based alloy including at least one member selected from among 0.01 to 10% Fe, 0.01 to 30% Ni and 0.01 to 25% Mn, which Co based alloy has a metal structure wherein ε-phase of h.c.p. structure having been generated by heat-induced or stress-induced transformation is formed in a ratio of 10 vol. % or more. According to necessity, there may be added at least one member selected from among 0.01 to 10% Al, 0.01 to 35% Cr, to 20% V, 0.01 to 15% Ti, 0.01 to 30% Mo, 0.01 to 10% Nb, to 3% Zr, 001 to 30% W, 0.01 to 10% Ta, 0.01 to 5% Hf, 0.01 to 8% Si, 0.001 to 3% C, 0.001 to 3% B, 0.001 to 3% P and 0.001 to 3% misch metal. The Co based alloy exhibits high elastic deformation capability and is good in ductility and workability. The Co based alloy is used as a functional material of, for example, sensor or actuator capable of displacement control by magnetic field application.

1 - 5 . (canceled) 
   
   
       6 . A material having a high elastic deformation composed of Co-based alloy comprising, on the basis of mass percent, one or more members selected from 0.01 to 10% of Fe, 0.01 to 30% of Ni, 0.01 to 25% of Mn, and the balance being cobalt without inevitable impurities, wherein
 the Co-based alloy is Co-based alloy having a high elastic deformation in which ε-phase of h.c.p. structure thermally induced and/or stress-induced from γ-phase of f.c.c. structure occupies 10% or more by volume of an total metallic structure.   
   
   
       7 . The material having the high elastic deformation according to  claim 6 , wherein the ε-phase occupies 99% or more by volume of the total metallic structure in the Co-based alloy. 
   
   
       8 . The material having the high elastic deformation according to  claim 7 , wherein the Co-based alloy contains two or more members selected from Fe, Ni, and Mn, and a contained amount thereof is in the range of 0.02 to 50%. 
   
   
       9 . The material having the high elastic deformation according to  claim 6 , wherein
 the Co-based alloy further comprises a third element which is one or more members selected from 0.01 to 10% of Al, 0.01 to 35% of Cr, 0.01 to 20% of V, 0.01 to 15% of Ti, 0.01 to 30% of Mo, 0.01 to 10% of Nb, 0.01 to 3% of Zr, 0.01 to 30% of W, 0.01 to 10% of Ta, 0.01 to 5% of Hf, 0.01 to 8% of Si, 0.001 to 3% of C, 0.001 to 3% of B, 0.001 to 3% of P, and 0.001 to 3% of misch metal.   
   
   
       10 . The material having the high elastic deformation according to  claim 9 , wherein
 the Co-based alloy contains at least two members as the third element, and a contained   
   
   
       11 . The material having the high elastic deformation according to  claim 10 , wherein
 the Co-based alloy has an intensity of magnetization of 30 emu/g or more relative to an external magnetic field of 0.2 T.   
   
   
       12 . The material having the high elastic deformation according to  claim 11 , wherein
 the Co-based alloy comprises any of an inter-metal compound layer by an additional element, α-phase, carbide, boride, and phosphide other than the γ-phase and the ε-phase.   
   
   
       13 . A process of producing a material having a high elastic deformation, wherein
 Co-based alloy including, on the basis of mass percent, one or more members selected from 0.01 to 10% of Fe, 0.01 to 30% of Ni, and 0.01 to 25% of Mn, and the balance being cobalt without inevitable impurities, is first subjected to solution treatment at 900 to 1,400° C., and   ε-phase of h.c.p. structure is then thermally induced and/or stress-induced.   
   
   
       14 . The process of producing the material having a high elastic deformation according to  claim 13 , wherein
 the ε-phase of the h.c.p. structure is stress-induced at a working ratio of 10 to 90% in the Co-based alloy after the solution treatment.   
   
   
       15 . The process of producing the material having a high elastic deformation according to  claim 14 , wherein
 the ε-phase of the h.c.p. structure is thermally induced after the reduced Co-based alloy is subjected to aging treatment at 300 to 800° C.   
   
   
       16 . The process of producing the material having a high elastic deformation according to  claim 13 , wherein
 the Co-based alloy further comprises a third element which is one or more members selected from 0.01 to 10% of Al, 0.01 to 35% of Cr, 0.01 to 20% of V, 0.01 to 15% of Ti, 0.01 to 30% of Mo, 0.01 to 10% of Nb, 0.01 to 3% of Zr, 0.01 to 30% of W, 0.01 to 10% of Ta, 0.01 to 5% of Hf, 0.01 to 8% of Si, 0.001 to 3% of C, 0.001 to 3% of B, 0.001 to 3% of P, and 0.001 to 3% of misch metal.