# US 6,001,304 A · Method of bonding a particle material to near theoretical density > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,001,304 A - Document ID: US6001304A - Status: Granted - Kind: A - Application number: 09/223,964 - Filed: 1998-12-31 - Granted: 1999-12-14 - Earliest claimed: 1998-12-31 - Assignees: Materials Modification, Inc. - Inventors: Sang H. Yoo; Krupashankara M. Sethuram; Tirumalai S. Sudarshan - Web page: https://patentgrep.com/patent/US6001304A ## CPC - C04B 35/58092: {based on refractory metal silicides} - B01J 3/06: Processes using ultra-high pressure, e.g. for the formation of diamonds; Apparatus therefor, e.g. moulds or dies (B01J3/04 takes precedence) - B01J 3/062: {characterised by the composition of the materials to be processed} - B01J 19/087: {employing electric or magnetic energy} - B22F 3/105: by using electric current {other than for infrared radiant energy}, laser radiation or plasma (B22F3/11 takes precedence){; by ultrasonic bonding (B22F3/115 takes precedence)} - B30B 15/34: Heating or cooling presses or parts thereof - B32B 18/00: Layered products essentially comprising ceramics, e.g. refractory products - C04B 35/52: based on carbon, e.g. graphite - C04B 35/571: obtained from {Si-containing} polymer precursors {or organosilicon monomers} - C04B 35/58071: {based on titanium borides} - C04B 35/581: based on aluminium nitride - C04B 35/645: Pressure sintering - C04B 35/6455: {Hot isostatic pressing} - C04B 37/001: {directly with other burned ceramic articles} - B01J 2203/062: Diamond - B01J 2203/0655: Diamond - B01J 2203/0685: Crystal sintering - B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy - C04B 2235/6567: Treatment time - C04B 2237/343: Alumina or aluminates - C04B 2237/365: Silicon carbide - Y10S 29/031: Pressing powder with other step - Y10S 977/777: Metallic powder or flake - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - B30B: PRESSES IN GENERAL (producing ultra-high pressure or ultra-high pressure and high temperature to effect modifications of a substance, e.g. for making artificial diamonds B01J3/00 ){(compressing means for refuse receptacles B65F1/1405)} - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A method of bonding a particle material to near theoretical density, includes placing a particle material in a die. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps, is applied. The method can be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material. The method may also be applied to perform combustion synthesis of a reactive material, followed by consolidation or joining to near-net shaped articles or parts. The method may further be applied to repair a damaged or worn substrate or part, coat a particle onto a substrate, and grow single crystals of a particle material. ## Claims ### Claim 1 A method of bonding a particle material to near theoretical density, comprising the steps of: a) providing a chamber; b) placing a particle material to be bonded in the chamber; c) applying a shear force to the particle material for a predetermined time period; d) substantially simultaneously with the step c) application of shear force, applying a pulsed current to the particle material for a predetermined time period; e) applying a pressure to the particle material; and f) substantially simultaneously with the step e) application of pressure, applying a steady current to the particle material for bonding the particle material. ### Claim 2 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a pulsed current of about 1-20,000 amps. ### Claim 3 (depends on 2) The method of claim 2, wherein: the step d) comprises applying a pulsed current of about 1-8,000 amps. ### Claim 4 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a voltage of about 1-100 volts. ### Claim 5 (depends on 4) The method of claim 4, wherein: the step d) comprises applying a voltage of about 1-30 volts. ### Claim 6 (depends on 1) The method of claim 1, wherein. the step d) comprises applying a current having a pulsing frequency of about 1-1000 Hz. ### Claim 7 (depends on 6) The method of claim 6, wherein: the step d) comprises applying a current having a pulsing frequency of about 10-100 Hz. ### Claim 8 (depends on 6) The method of claim 6, wherein: the pulsing duration in step d) is about less than 1-600 minutes. ### Claim 9 (depends on 8) The method of claim 8, wherein: the pulsing duration in step d) is about 5-30 minutes. ### Claim 10 (depends on 1) The method of claim 1, wherein: the chamber comprises at least one plunger. ### Claim 11 (depends on 10) The method of claim 10, wherein: the chamber comprises top and bottom plungers; and the step c) application of shear force comprises rotating the top plunger in one direction and the bottom plunger in a second direction opposite to the first direction. ### Claim 12 (depends on 11) The method of claim 11, wherein: the top and bottom plungers are rotated at a speed of about 1-10 revolutions/min. ### Claim 13 (depends on 1) The method of claim 1, wherein: the step c) comprises applying a shear force of about 5-50 MPa. ### Claim 14 (depends on 1) The method of claim 1, wherein: the chamber comprises a graphite or carbon-carbon composite die. ### Claim 15 (depends on 1) The method of claim 1, wherein: the step e) comprises applying an axial pressure of about less than 1-2,000 MPa. ### Claim 16 (depends on 15) The method of claim 15, wherein: the step e) comprises applying an axial pressure of about 10-200 MPa. ### Claim 17 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a current of about 1-20,000 amps. ### Claim 18 (depends on 17) The method of claim 17, wherein: the step f) comprises applying a current of about 1-8,000 amps. ### Claim 19 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a current for a duration of about less than 1-600 minutes. ### Claim 20 (depends on 19) The method of claim 19, wherein: the step f) comprises applying a current for a duration of about 5-30 minutes. ### Claim 21 (depends on 1) The method of claim 1, wherein: the step f) comprises heating the particle material to a temperature of about 25.degree. C.-3,000.degree. C. ### Claim 22 (depends on 1) The method of claim 1, wherein: the step f) comprises heating the particle material to a temperature of about 25.degree. C.-2,500.degree. C. ### Claim 23 (depends on 1) The method of claim 1, wherein: the particle material comprises a precursor or elemental particle material selected from the group consisting of metallic material, ceramic material, intermetallic material, alloy, composite material, coated powder, uncoated powder, porous material, partially dense substrate, and fully dense substrate. ### Claim 24 (depends on 23) The method of claim 23, wherein: the metallic material is selected from the group consisting of iron, copper, cobalt, nickel, tungsten, rhenium, and molybdenum. ### Claim 25 (depends on 23) The method of claim 23, wherein: the ceramic material is selected from the group consisting of silicon carbide, boron carbide, boron nitride, alumina, aluminum nitride, titanium dioxide, titanium diboride and aluminum dioxide. ### Claim 26 (depends on 23) The method of claim 23, wherein: the intermetallic material is selected from the group consisting of iron, iron aluminide and molybdenum disilicide. ### Claim 27 (depends on 23) The method of claim 23, wherein: the composite material is selected from group consisting of tungsten carbide-cobalt, tungsten-copper, molybdenum-copper, and iron cobalt-silicon carbide. ### Claim 28 (depends on 1) The method of claim 1, wherein: the particle material comprises diamond or coated diamond powder. ### Claim 29 (depends on 1) The method of claim 1, wherein: the particle material comprises powder particles having an average particle size of about 100 microns to less than 0.01 microns. ### Claim 30 (depends on 1) The method of claim 1, wherein: the chamber comprises a die; and the step d) comprises applying a pulsed current to the particle material directly through the die. ### Claim 31 (depends on 1) The method of claim 1, wherein: the bonded particle material comprises a density of about 95% or higher. ### Claim 32 (depends on 1) The method of claim 1, wherein: The bonded particle material comprises a density of about 99% or higher. ### Claim 33 (depends on 1) The method of claim 1, wherein: the step c) comprises applying a shear force for a duration of about less than 1-15 minutes. ### Claim 34 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a voltage selected from the group consisting of pulsed D.C. voltage, alternating pulsed D.C. voltage, and a combination thereof; and the step f) comprises applying a voltage selected from the group consisting of D.C. voltage, alternating D.C. voltage, and a combination thereof. ### Claim 35 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a base line voltage of about 1-99 volts. ### Claim 36 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a base line voltage of about 1-99 volts. ### Claim 37 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a peak current of about 5-20,000 amps. ### Claim 38 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a peak current of about 200-20,000 amps. ### Claim 39 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a base line current of about 0-14,000 amps. ### Claim 40 (depends on 1) The method of claim 1, wherein: the step d) comprises applying a base line current of about 0-14,000 amps. ### Claim 41 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a peak current of about 5-20,000 amps. ### Claim 42 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a peak current of about 200-20,000 amps. ### Claim 43 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a base line current of about 0-14,000 amps. ### Claim 44 (depends on 1) The method of claim 1, wherein: the step f) comprises applying a base line current of about 0-4,000 amps. ### Claim 45 (depends on 1) The method of claim 1, wherein: the duty cycle for application of the current in either step d) or f) is about 1-100%. ### Claim 46 (depends on 1) The method of claim 1, wherein. the duty cycle for application of the voltage in either step d) or f) is about 1-100%. ### Claim 47 (depends on 1) The method of claim 1, wherein: the step c) application of shear force comprises applying a pressure using hydraulic means, pneumatic means, an electric field, a magnetic field, or a combination thereof. ### Claim 48 (depends on 1) The method of claim 1, wherein: the step e) application of pressure comprises applying a pressure using hydraulic means, pneumatic means, an electric field, a magnetic field, or a combination thereof. ### Claim 49 (depends on 1) The method of claim 1, wherein: bonding of the particle material is carried out in the absence of a binder or an additive. ### Claim 50 (depends on 1) The method of claim 1, wherein: the step d) comprises surface activation of the particle material to thereby lower the oxygen content thereof. ### Claim 51 (depends on 1) A bonded material made in accordance with the method of claim 1. ### Claim 52 (depends on 51) The bonded material of claim 51, comprising a density of about 95% or higher. ### Claim 53 (depends on 51) The bonded material of claim 51, comprising a density of about 99% or higher. ### Claim 54 (depends on 52) The bonded material of claim 52, comprising a length of about less than one-half to six inches. ### Claim 55 (depends on 52) The bonded material of claim 52, comprising a diameter of about less than one-half to six inches. ### Claim 56 (depends on 51) The bonded material of claim 51, comprising a cylindrical, cubic, rectangular, tubular, or hemispherical shape. ### Claim 57 (depends on 1) The method of claim 1, wherein: the particle material is selected from the group consisting of a powder material, a substantially solid material, a precursor material, uncoated particles, and coated particles. ### Claim 58 (depends on 1) The method of claim 1, further comprising the step of: drawing a vacuum in the chamber prior to step c). ### Claim 59 (depends on 1) The method of claim 1, further comprising the step of: injecting a gas in the chamber prior to step c). ### Claim 60 (depends on 59) The method of claim 59, wherein: the gas comprises an inert gas or a reactive gas. ### Claim 61 (depends on 60) The method of claim 60, wherein: the reactive gas is selected from the group consisting of nitrogen, ammonia, methane, oxygen, and hydrogen. ### Claim 62 A method of bonding a particle material to near theoretical density, comprising the steps of: a) providing a chamber; b) placing a particle material to be bonded in the chamber; c) applying a shear force of about 5-50 MPa to the particle material for a duration of about less than 1-15 minutes; d) substantially simultaneously with the step c) application of shear force, applying a pulsed current of from about 1-20,000 amps. to the particle material for a duration of about less than 1-600 minutes; e) applying an axial pressure of about 1-2,000 MPa to the particle material; and f) substantially simultaneously with the step e) application of pressure, applying a steady current of about 1-20,000 amps. to the particle material for a duration of about 1-600 minutes to bond the particle material. ### Claim 63 (depends on 62) The method of claim 62, wherein: the particle material is selected from the group consisting of metallic material, ceramic material, intermetallic material, alloy, composite material, coated powder, uncoated powder, porous material, partially dense substrate, and fully dense substrate. ### Claim 64 (depends on 63) The method of claim 63, wherein: the step d) comprises applying a pulsed current of about 1-8,000 amps. for a duration of about 5-30 minutes. ### Claim 65 (depends on 64) The method of claim 64, wherein: the step e) comprises applying an axial pressure of about 10-200 MPa. ### Claim 66 (depends on 65) The method of claim 65, wherein: the step f) comprises applying a steady current of about 1-8,000 amps. for a duration of from about 5-30 minutes. ### Claim 67 (depends on 62) The method of claim 62, further comprising the step of: drawing a vacuum in the chamber prior to step c). ### Claim 68 (depends on 62) The method of claim 62, further comprising the step of: injecting an inert or reactive gas in the chamber prior to step c). ### Claim 69 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a voltage selected from the group consisting of pulsed D.C. voltage, alternating pulsed D.C. voltage, and a combination thereof; and the step f) comprises applying a voltage selected from the group consisting of D.C. voltage, alternating D.C. voltage, and a combination thereof. ### Claim 70 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a base line voltage of about 1-99 volts. ### Claim 71 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a base line voltage of about 1-99 volts. ### Claim 72 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a peak current of about 5-20,000 amps. ### Claim 73 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a peak current of about 200-20,000 amps. ### Claim 74 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a base line current of about 0-14,000 amps. ### Claim 75 (depends on 62) The method of claim 62, wherein: the step d) comprises applying a base line current of about 0-4,000 amps. ### Claim 76 (depends on 62) The method of claim 62, wherein: the step f) comprises applying a peak current of about 5-20,000 amps. ### Claim 77 (depends on 62) The method of claim 62, wherein: the step f) comprises applying a peak current of about 200-20,000 amps. ### Claim 78 (depends on 62) The method of claim 62, wherein: the step f) comprises applying a base line current of about 0-14,000 amps. ### Claim 79 (depends on 62) The method of claim 62, wherein: the step f) comprises applying a base line current of about 0-4,000 amps. ### Claim 80 (depends on 62) The method of claim 62, wherein: the duty cycle for application of the current in either step d) or f) is about 1-100%. ### Claim 81 (depends on 62) The method of claim 62, wherein: the duty cycle for application of the voltage in either step d) or f) is about 1-100%. ### Claim 82 (depends on 62) The method of claim 62, wherein: the step c) application of shear force comprises applying a pressure using hydraulic means, pneumatic means, an electric field, a magnetic field, or a combination thereof. ### Claim 83 (depends on 62) The method of claim 62, wherein: the step e) application of pressure comprises applying a pressure using hydraulic means, pneumatic means, an electric field, a magnetic field, or a combination thereof. ### Claim 84 (depends on 62) The method of claim 62, wherein: bonding of the particle material is carried out in the absence of a binder or an additive. ### Claim 85 (depends on 62) The method of claim 62, wherein: the step d) comprises surface activation of the particle material to thereby lower the oxygen content thereof.