General Electric Company

Alan I Taub

Shyh-Chin Huang

Keh-Minn Chang

Peter G Frischmann

Minyoung Lee

Mark Lloyd Miller

Harvey E Cline

Donald E Ballard

Louis E Hibbs, Jr

Thomas E Douglas

A method for contraction annealing niobium-tin wire is disclosed. An improved niobium-tin wire is provided by loosely winding the wire on a mandrel, or by coiling the wire on a circumferentially retractile mandrel, and contraction annealing the wire without reaction-forming substantial amounts of Nb.sub.3 Sn. Such contraction annealing allows the wire to contract in length unconstrained thereby preventing the formation of internal tensile stresses in the wire and its surrounding insulation. Prevention of internal stresses in the wire greatly reduces the susceptibility of the wire to breakage, cracking, sintering, shorting, tin leakage, or substantial shifting of the wire from desired wrap positions when it is reaction annealed to form the brittle super-conducting intermetallic compound Nb.sub.3 Sn.

Length stabilized Nb-Sn wire and annealing method

A method and apparatus for severing a stack of amorphous alloy ribbons in a softened state is disclosed. The method provides a smooth burr-free edge of close dimensional tolerance while preserving the desirable magnetic properties of the alloy. Resistance self-heating is applied to heat a localized portion of the stack to a temperature above the softening temperature of the alloy. Severing occurs adjacent the electrodes in an adjacent stack portion which is heated by diffusion from the directly heated stock portion.

Hot shear cutting of amorphous alloy ribbon

A method and apparatus for parting a deck of amorphous alloy ribbons in one operation is disclosed. Force is applied to a deck of ribbons to place it under tension. A localized zone in the deck is compressed and rapidly heated to the softening temperature of the amorphous alloy. The deck separates along a seam within the zone due to the tensile force and localized rapid heating. A high quality edge is produced where the separated ribbon edges are free of burrs, meltbeads or substantial cracking and chipping.

Method and apparatus for parting a deck of amorphous alloy ribbons

A method for contraction annealing niobium-tin wire is disclosed. An improved niobium-tin wire is provided by loosely winding the wire on a mandrel, or by coiling the wire on a circumferentially retractile mandrel, and contraction annealing the wire without reaction-forming substantial amounts of Nb.sub.3 Sn. Such contraction annealing allows the wire to contract in length unconstrained thereby preventing the formation of internal tensile stresses in the wire and its surrounding insulation. Prevention of internal stresses in the wire greatly reduces the susceptibility of the wire to breakage, cracking, sintering, shorting, tin leakage, or substantial shifting of the wire from desired wrap positions when it is reaction annealed to form the brittle superconducting intermetallic compound Nb.sub.3 Sn.

Contraction pre-annealing superconducting wire for length stabilization

For shear-cutting a stack of thin sheets of amorphous steel along a cutting plane that extends transversely of the stack, we utilize apparatus that comprises two blades that are positioned at the start of a cutting operation on opposite sides of the stack. Each of the blades has a first surface for engaging one side of the stack and a second surface extending transversely of the first surface and generally parallel to said cutting plane and intersecting the first surface at a corner. The first surface of each blade is disposed at a predetermined rake angle with respect to a reference plane extending through a point on the corner of the blade and normal to said cutting plane. By making the sum of these rake angles of a negative value and beween 5 and 35 degrees, we are able to substantially improve the wear resistance of the blades and lengthen their working life.

Apparatus for shear-cutting a stack of amorphous steel sheets

Ni.sub.3 A1 alloy of improved ductility based on iron and niobium

Ni.sub.3 Al alloy of improved ductility based on iron substituent

It had been found previously that tri-nickel aluminide compositions are quite sensitive to the ratio of nickel to aluminum in their ability to receive boron as a dopant. It has now been found that compositions which are relatively poor in the aluminum component can be doped more effectively with a combination of boron and zirconium. It has been found for the nickel aluminides which have lower concentrations of aluminum that the percent of zirconium and boron which can be added to the composition to effectively increase the strength of the alloys is favored by the lower aluminum ratio. The compositions which result are found to have significant strength properties not only at room temperature but at elevated temperatures based on tensile tests of the compositions.

Rapidly solidified zirconium modified nickel aluminide of improved

A tri-nickel aluminide base alloy composition is provided with a desirable combination of tensile strength and ductility. The composition is prepared to include boron dopant in combination with relatively low percentages of carbon for the high increase in strength achieved. The composition has an Ll.sub.2 of crystalline structure. It is prepared by rapid solidification at a cooling rate of at least 10.sup.3 .degree. C. per second.

Carbon containing boron doped tri-nickel aluminide

The problem of working an amorphous alloy is overcome by heating the alloy at a rate of temperature increase above about 1000.degree. C. per minute. The amorphous alloy is worked by homogeneous deformation after its temperature has been very rapidly increased to above the softening temperature of the alloy. Desirable magnetic properties of the alloy are preserved by working the alloy in this fashion and also tool life is extended.

Isothermal hold method of hot working of amorphous alloys

A method for achieving both improved strength and improved ductility in intermediate phases is provided. The method, briefly stated, comprises the steps of providing a melt whose composition substantially corresponds to that of a preselected intermetallic phase having a crystal structure of the Ll.sub.2 type, such as nickel alumininde, modified with from about 0.01 to 2.5 atomic percent boron, and modified further with cobalt substituent metal and rapidly solidifying the melt at a cooling rate of at least about 10.sup.3 .degree. C./second to form a solid body, the principal phase of which is of the Ll.sub.2 type crystal structure in either its ordered or disordered state.

Rapidly solidified tri-nickel aluminide base alloy

Improvements in the positive temperature dependence of yield strength and in the work hardening rate of tri-nickel aluminide base alloys are achieved. The novel alloy composition has seven alloying ingredients as follows:

Cold worked tri-nickel aluminide alloy compositions

A bundle of articles having at least one small dimension are cut in succession. Tension is developed on the top article of the bundle. Heat is applied rapidly to a seam of the top article to be cut. The separated parts of a top article are withdrawn from the path of the beam and the next article is exposed to the heat.

Heat assisted parting of amorphous alloys

A substantial increase in strength of a boron doped nickel aluminide is achieved by employing a substituent metal in the Ni.sub.3 Al composition to replace a part of the aluminum. Vanadium and silicon are successfully substituted for a portion of the aluminum to provide a composition:

Rapidly solidified nickel aluminide alloy

A metal body having high tensile strength and ductility at temperatures over 1000.degree. F. is provided. The body is prepared by hot isostatic pressing of powder formed by atomization of a melt of an alloy. The alloy composition base is according to the formula:

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Schenectady, NY, United States of America

Alan I Taub