Nanocrystal dispersed amorphous alloys

Details Nanocrystal dispersed amorphous alloys Nanocrystal dispersed amorphous alloys

1998-10-21

2001-07-17

Wyszomierski, George (Department: 1742)

Metal treatment

Stock

Magnetic

C148S305000, C148S403000, C148S437000

Reexamination Certificate

active

06261386

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of amorphous alloys. More particularly, the present invention relates to amorphous alloys and alloy structures obtained by controlled crystallization. Specifically, a preferred implementation of the present invention relates to alloys with high number density nanocrystal dispersions that are seeded with an element that is added to the amorphous matrix but that is insoluble therewith. The present invention thus relates to amorphous alloys of the type that can be termed nanocrystal dispersed.
2. Discussion of the Related Art
Historically, rapid solidification processing has yielded amorphous structures in numerous metallic alloy systems. The development of nanocrystalline materials through the partial recrystalization (devitrification) of amorphous precursors has recently received considerable attention.
A first class of amorphous metallic materials that shows particular promise for commercial applications consists of aluminum (Al) glasses that include transition metal (TM) and rare earth (RE) elements. These aluminum glasses possess exceptional strength combined with good ductility and corrosion resistance. These Al-TM-RE glasses typically contain greater than 75 atomic percent (at. %) aluminum. These Al-TM-RE glasses offer an alternative to traditional crystalline materials for some structural applications.
A second class of amorphous metallic materials that shows particular promise for commercial applications consists of iron (Fe) glasses that include transition metal (TM) and rare earth (RE) elements together with boron (B). These iron glasses possess good magnetic properties for electrical applications. These Fe-TM-RE-B glasses typically contain greater than 70 at. % iron.
Those of skill in the art of materials know that changing the size and density of nanocrystals that are produced during initial devitrification can alter the properties of both of these classes of amorphous metallic materials. The controlled crystallization of these alloys is a challenge, as the prior art alloying and heat treatment techniques have remained strictly empirical. Heretofore, there has been no effective approach to precisely and accurately control the number density or dispersion of nanocrystals in an amorphous matrix.
Within this application several publications are referenced by Arabic numerals within brackets. Full citations for these, and other, publications may be found at the end of the specification immediately preceding the claims. The disclosures of all these publications in their entireties are hereby expressly incorporated by reference into the present application for the purposes of indicating the background of the present invention and illustrating the state of the art.
SUMMARY OF THE INVENTION
Thus, there is a need for a phase separation technique that yields a high number density distribution of fine scale discrete particles in an amorphous matrix. Further, there is a particular need for a technique that yields a predictable and reproducible dispersion of such particles. The particles are used as nucleation sites for nanocrystal formation during subsequent devitrification. The characteristics of the resulting amorphous alloy are a function of the characteristics of the nanocrystals and the characteristics of the nanocrystals are a function of the characteristics of the particle dispersion. Unexpected beneficial effects of the present invention, which are substantial improvements over the prior art, include higher strength in the case of aluminum based amorphous alloys, and in the case of iron based amorphous alloys, better magnetic properties.
These, and other, aspects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating preferred embodiments of the present invention and numerous specific details thereof, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.


REFERENCES:
patent: 4416709 (1983-11-01), Ohya et al.
patent: 4470723 (1988-09-01), Sagawa et al.
patent: 4495691 (1985-01-01), Masumoto et al.
patent: 4523626 (1985-06-01), Masumoto et al.
patent: 4668310 (1987-05-01), Kudo et al.
patent: 4735864 (1988-04-01), Masumoto et al.
patent: 4909867 (1990-03-01), Masumoto et al.
patent: 4911767 (1990-03-01), Masumoto et al.
patent: 4950452 (1990-08-01), Masumoto et al.
patent: 5032196 (1991-07-01), Masumoto et al.
patent: 5053084 (1991-10-01), Masumoto et al.
patent: 5074935 (1991-12-01), Masumoto et al.
patent: 5122205 (1992-06-01), Masumoto et al.
patent: 5198042 (1993-03-01), Masumoto et al.
patent: 5209791 (1993-05-01), Masumoto et al.
patent: 5213148 (1993-05-01), Masumoto et al.
patent: 5240517 (1993-08-01), Masumoto et al.
patent: 5288344 (1994-02-01), Peker et al.
patent: 5296059 (1994-03-01), Masumoto et al.
patent: 5466308 (1995-11-01), Fujimura et al.
patent: 5611871 (1997-03-01), Yoshizawa et al.
patent: 5714018 (1998-02-01), Kita et al.
patent: 6019859 (2000-02-01), Kanekiyo et al.
Foley, J. et al., “Formation of Nanocrystalline Aluminum in Al-Y-FE Amorphous Alloys”,Materials Science Forum, vols. 225-227 (1996) pp. 323-328.
Foley, J. et al., “Analysis of Nanocrystal Development in Al-Y-Fe and Al-Sm Glasses”,Scripta Materialia, vol. 35, No. 5, pp. 655-660, 1990.
Yeum, K. et al., “Estimation of the Surface Tensions of Binary Liquid Alloys”,Metallurgical Transactions B, vol. 20B, Oct. 1989, pp. 693-703.
He, Y. et al., “Unique Metallic Glass Formability and Ultra-High Tensile Strength in Al-Fe-Gd Alloys”,Acta metall. mater., vol. 41, No. 2, pp. 337-343 (1993).
Inoue, A. et al. “Light-metal base amorphous alloys containing lanthanide metal”,Journal of Alloys and Compounds, vols. 207/208, pp. 340-348 (1994).
Makino, A. et al., “Magnetic properties and core losses of nanocrystalline Fe-M-B (M≡Zr, Hf or Nb) alloys”,Materials Science and Engineering, (1994) pp. 127-131.
Higashi, K. et al., “Very Fine Grains and Very High Strain Rate Superplasticity in Aluminum-Based Alloys Produced from Amorphous Powders”,Materials Science Forum, vols. 113-115 (1993), pp. 231-236.
Masumoto, T., “Recent Progress of Amorphous Metallic Materials”,Sci. Rep. RITU, (1994), pp. 91-102.
Diego, J. et al., “Thermodynamic, kinetic and structural mechanisms controlling the formation of nanocrystalline Nd-Fe-B materials”,Materials Science and Engineering, (1994), pp. 526-530.
Choi, G. et al., “Ultrahigh Tensile Strength of Amorphous Al-Ni-(Nd,Gd)-Fe Alloys Containing Nanocrystalline Al Particles”,Scripta Metallurgica et Materials, vol. 33, No. 8, pp. 1301-1306 (1995).
Inoue, A. et al., “Fe-Based Ferromagnetic Glassy Alloys with Wide Supercooled Liquid Region”,Materials Transactions JIM, vol. 36, No. 9, pp. 1180-1183 (1995).
Koster, U. et al., “Phase Transformations in Rapidly Solidified Alloys”,Rapidly Solidified Alloys, Liebermann, H. (Ed.), Marcel Dekker, Inc., New York, pp. 310-315.
Iida, T. et al., “The Physical Properties of Liquid Metals”, Clarendon Press, Oxford, 1993, pp. 135-147.
Suzuki, K. et al., “Changes in Microstructure and Soft Magnetic Properties of an Fe86Zr7B6Cu1Amorphous Alloy upon Crystallization”,Materials Transactions, JIM, vol. 32, No. 10 (1991), pp. 961-968.
Inoue, A., “High Strength Bulk Amorphous Alloys with Low Critical Cooling Rates (Overview)”,Materials Transactions, JIM, vol. 36, No. 7 (1995), pp. 866-875.
Makino, A. et al., “Low Core Loss of a bcc Fe86Zr7B6Cu1Alloy with Nanoscale Grain Size”,Materials Transactions, JIM, vol. 32, No. 6 (1991), pp. 551-556.
Inoue, A., “Nanocrystalline Soft Magnetic Alloys with Zero Magnetostrict Ion In Fe-Zr-Al and Fe-Zr-Si Base Systems”,Mat. Sci. Forum, vols. 225-227, p. 639 (1996).
Muller, K. et al., “TEM investigation of crystallization phenomena in the metallic gl

Affiliated with

Also associated with

Rating

Nanocrystal dispersed amorphous alloys does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Nanocrystal dispersed amorphous alloys, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nanocrystal dispersed amorphous alloys will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2540617