Title: Alloy with metallic glass and quasi-crystalline properties

Abstract

An alloy is described that is capable of forming a metallic glass at moderate cooling rates and exhibits large plastic flow at ambient temperature. Preferably, the alloy has a composition of (Zr, Hf).sub.a Ta.sub.b Ti.sub.c Cu.sub.d Ni.sub.e Al.sub.f, where the composition ranges (in atomic percent) are 45.ltoreq.a.ltoreq.70, 3.ltoreq.b.ltoreq.7.5, 0.ltoreq.c.ltoreq.4, 3.ltoreq.b+c.ltoreq.10, 10.ltoreq.d.ltoreq.30, 0.ltoreq.e.ltoreq.20, 10.ltoreq.d+e.ltoreq.35, and 5.ltoreq.f.ltoreq.15. The alloy may be cast into a bulk solid with disordered atomic-scale structure, i.e., a metallic glass, by a variety of techniques including copper mold die casting and planar flow casting. The as-cast amorphous solid has good ductility while retaining all of the characteristic features of known metallic glasses, including a distinct glass transition, a supercooled liquid region, and an absence of long-range atomic order. The alloy may be used to form a composite structure including quasi-crystals embedded in an amorphous matrix. Such a composite quasi-crystalline structure has much higher mechanical strength than a crystalline structure.

Inventors:

Xing, Li-Qian; Hufnagel, Todd C.; Ramesh, Kaliat T.

Issue Date:

2004-02-17

Research Org.:

Johns Hopkins University, Baltimore, MD (United States)

Sponsoring Org.:

USDOE

OSTI Identifier:

1174730

Patent Number(s):

6692590

Application Number:

09/960,946

Assignee:

Johns Hopkins University (Baltimore, MD)

Patent Classifications (CPCs):

C - CHEMISTRY C22 - METALLURGY C22C - ALLOYS

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C - CHEMISTRY C22 - METALLURGY C22C - ALLOYS

C22C45/10 - with molybdenum, tungsten, niobium, tantalum, titanium, or zirconium {or Hf} as the major constituent

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DOE Contract Number:  

FG02-98ER45699

Resource Type:

Patent

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE