Method of making dispersion strengthened metal bodies and product
AssigneeSCM Corporation
InventorsAnil V. Nadkarni, Prasanna K. Samal, James C. Wang, James E. Sunk
Life of this patent
Estimating the term…
Abstract
A process and a product produced thereby, for forming rod or bar or tube stock or strip, comprising a sheath and a densified dispersion strengthened metal core. Powdered dispersion strengthened copper is put into a metal can and compressively reduced to size and density. The relationship between the tensile strength of the core when fully densified and the cold worked tensile strength of the can is important to the nature of the product.
Claims43
A process for forming an elongated member of substantially uniform cross-section and comprising a metal sheath surrounding a dispersion-strengthened metal core which comprises the steps of:
- (a) providing a sheath-forming metal container,
- (b) filling said container with dispersion strengthened metal powder having a particle size less than 20 mesh (Tyler Screen Size) and said dispersion strengthened metal containing from about 0.1% to about 5% by weight of a solute metal as a refractory oxide dispersed therein and having a predetermined tensile strength at full density,
- (c) the metal of said container having a tensile strength at room temperature in the cold worked condition no more than about 22% to 25% less than said predetermined tensile strength at full density of said core;
- and
- (d) reducing the cross-sectional area of the powder filled container by application of compressive force to said container in a plurality of reduction stages each in the range of from about 15% to about 35% of the cross-sectional area until a density of at least about 90% of theoretical density is achieved.
A process for forming an elongated member of substantially uniform cross-section and comprising a metal sheath surrounding a densified dispersion strengthened metal core which comprises the steps of:
- (a) providing a sheath-forming metal container;
- (b) filling said container with dispersion strengthened metal powder having a particle size less than 20 mesh (Tyler Screen Size) and said dispersion strengthened metal containing from about 0.1% to about 5.0% by weight of a solute metal as a refractory oxide dispersed therein and having a tensile strength at full density of at least about 55,000 psi at room temperature;
- (c) the metal of said container having a tensile strength at room temperature in the cold worked condition of not more than about 15,000 psi less than the tensile strength of said densified dispersion strengthened metal at maximum density;
- and
- (d) reducing the cross-sectional area of the powder filled container by application of compressive force to said container in a plurality of reduction stages each in the range of from about 15% to about 35% of the cross-sectional area until a density of at least about 90% of theoretical density is achieved.
A bar, tube or strip of substantially uniform cross section comprising a metal sheath in tightly adhering relation with a densified dispersion strengthened copper core, said dispersion strengthened copper core containing from about 0.1% to about 4.0% by weight of a metal as a refractory oxide dispersed therein, said core having a tensile strength of at least about 55,000 pounds at room temperature and said sheath having a tensile strength of at least about 40,000 psi at room temperature.
A resistance welding electrode having a proximal end and a distal end and formed from a swaged bar and comprising (a) a cylindrical portion characterized by a core of internally oxidized dispersion strengthened copper containing from 0.1 to 4.0% aluminum as refractory aluminum oxide dispersed therein, said core having an ultimate tensile strength developed during swaging to full density of at least about 55,000 psi, said cylindrical portion also having a thin metal sheath surrounding and tightly adhering to said core, said sheath having a cold worked tensile strength at room temperature no more than 15,000 psi below the ultimate tensile strength of said core, said cylindrical body also including a recessed water hole in the proximal end thereof, and (b) a tip portion characterized by converging side surfaces terminating in a circular work-contacting tip, the plan of said circular tip being normal to the longitudinal axis of said electrode.
A magnetically responsive wire product having an outer sheath of copper, a contiguous inner ferruginous annulus and a core of fully densified internally oxidized dispersion strengthened copper filling said inner annulus, said core containing from 0.1% to 0.7% aluminum as refractory aluminum oxide dispersed therein.
A process for forming an elongated member of substantially uniform cross-section and comprising a metal sheath surrounding a dispersion strengthened metal core which comprises the steps of:
- (a) providing a sheath-forming metal container,
- (b) filling said container with a metal powder comprising dispersion strengthened metal powder and having a particle size less than 20 mesh (Tyler Screen Size) and said dispersion strengthened metal containing from about 0.1% to about 5% by weight of a solute metal as a refractory oxide dispersed therein and having a predetermined tensile strength at full density,
- (c) the metal of said container having a tensile strength at room temperature in the cold worked condition no more than about 22% to 25% less than said predetermined tensile strength at full density of said core;
- and
- (d) reducing the cross-sectional area of the powder filled container by application of compressive force to said container in a plurality of reduction stages each in the range of from about 15% to about 35% of the cross-sectional area until a density of at least about 90% of theoretical density is achieved.
Dependencies are inferred from the claim text.