US3890690A
Expired / Lapsed
US
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Method of making reinforced metal matrix composites having improved load transfer characteristics and reduced mismatch stresses
Assignee: Individual
•
Filing: 1972-05-04
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Granted: 1975-06-24
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Expires: 1992-05-04
Abstract
Abstract The method for making reinforced, metal-matrix composite, comprises: preparing elongated, high-strength and high-modulus reinforcing members; dispersing the members is spatial relationship in a strain-hardenable metal matrix; effectively bonding the members to the surrounding matrix at selected, discrete surface regions along their lengths; and stressing the composite sufficiently to locally strain the matrix near the discretely bonded regions. The matrix in the space between the members is then substantially and nonuniformly strain-hardened and strengthened. Also, the spheres of influence induced by the straining and stain-hardening in the matrix near one member are caused to significantly overlap similar spheres of influence near the neighboring members, so as to substantially increase the load transfer ability between the members through the intervening hardened and strengthened matrix.
Inventors
- 👤 Chou H Li
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:25
CPC Classifications
C; C22; C22C; C22C47/00; C22C47/02; C22C47/06; C22C47/062; C22C47/068; Y; Y10; Y10S; Y10S29/00; Y10S29/049; Y10T; Y10T29/00; Y10T29/49; Y10T29/49758; Y10T29/49801; Y10T428/00; Y10T428/12; Y10T428/12326; Y10T428/1234; Y10T428/12465; Y10T428/12486; Y10T428/12493; Y10T428/12639; Y10T428/12729; Y10T428/12736; Y10T428/1275; Y10T428/12757; Y10T428/12771; Y10T428/12778; Y10T428/12861; Y10T428/12903; Y10T428/12917; Y10T428/12924; Y10T428/24; Y10T428/24752; Y10T428/249921; Y10T428/249924; Y10T428/249927; Y10T428/29; Y10T428/2913; Y10T428/2973; Y10T428/2976
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
141 words
The method for making reinforced, metal-matrix composite, comprising: preparing a plurality of elongated, high-strength and high-modulus reinforcing members; dispersing the members in spatial relationship in a strain-hardenable metal matrix; effectively bonding the members to the surrounding matrix at selected, discrete surface regions along their lengths; and stressing the composite sufficiently to locally strain the matrix near the discretely bonded regions whereby the matrix in the space between the members is substantially and selectively though nonuniformly strain-hardened and strengthened and whereby spheres of influence induced by the straining and strain-hardening in the matrix within the space near the discrete regions on one member are caused to significantly overlap similar spheres of influences near the neighboring members so as to substantially increase mechanical interaction and load transfer ability between the one member and the neighboring members through the intervening hardened and strengthened matrix.
Claim 2
Independent Claim
141 words
The method for making reinforced, metal-matrix composite, comprising: preparing a plurality of elongated, high-strength and high-modulus reinforcing members; dispersing the members in spatial relationship in a strain-hardenable metal matrix; effectively bonding the members to the surrounding matrix at selected, discrete surface regions along their lengths; and stressing the composite sufficiently to locally strain the matrix near the discretely bonded regions whereby the matrix in the space between the members is substantially and selectively though nonuniformly strain-hardened and strengthened and whereby spheres of influence induced by the straining and strain-hardening in the matrix within the space near the discrete regions on one member are caused to significantly overlap similar spheres of influences near the neighboring members so as to substantially increase mechanical interaction and load transfer ability between the one member and the neighboring members through the intervening hardened and strengthened matrix.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein the bonding step comprises varying the character of bonding periodically along the length of the members.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein the bonding step comprises alternately chemically and physically bonding the matrix to the members along their lengths.
Claim 5
Dependent Claim
42 words
The method of claim 1 wherein the members have appreciable, difficult-to-wet surface materials thereon, and the preparing step includes applying a bond-promoting chemical on selected surface areas of the members, the selected areas generally coinciding with the subsequently formed, discretly bonded regions.
Claim 6
Dependent Claim
59 words
The method of claim 1 wherein the preparing, dispersing, and bonding steps are accomplished in a single operation by means of a chemical phase transformation involving at least three distinct phases capable of establishing thermodynamic equilibrium at a transformation temperature, the transformation occurring at the temperature and the three phases including at least one fluid phase at the temperature.
Claim 7
Dependent Claim
24 words
The method of claim 1 wherein the preparing, dispersing, and bonding steps are accomplished in a single operation by means of eutectic melt growth.
Claim 8
Dependent Claim
32 words
The method of claim 1 wherein the bonding step comprises effectively bonding to the matrix at substantially equally spaced and similarly shaped discrete regions along the length of each of the members.
Claim 9
Dependent Claim
29 words
The method of claim 7 wherein the dispersing step comprises orienting the members generally in the direction of the intended principle tensile loading on the composite when in use.
Claim 10
Dependent Claim
26 words
The method of claim 1 wherein the preparing step comprises periodically and substantially varying the transverse section thickness of each of the members along its length.
Claim 11
Dependent Claim
45 words
The method of claim 9 wherein the periodic transverse thickness variation includes within each period a transverse plane of substantially constant but extreme section thickness, and wherein the bonding step comprises bonding to the matrix the members in discrete regions generally centered on the planes.
Claim 12
Dependent Claim
29 words
The method of claim 1 wherein the preparing step comprises periodically forming along the length of the members protrusions having sufficient sizes to significantLy affect the spheres of influence.
Claim 13
Dependent Claim
24 words
The method of claim 11 wherein the bonding step comprises limiting the chemical bonding of the matrix to only the surfaces of the protrusion.
Claim 14
Dependent Claim
40 words
The method of claim 11 wherein the bonding step comprises bonding to the matrix the non-protruded portions of the members imperfectly to the extent to allow absorption therein of thermoplastic mismatch stresses and strains between the members and the matrix.
Claim 15
Dependent Claim
36 words
The method of claim 11 wherein the preparing step comprises applying on each non-protruded portion of the members a protective inert layer to prevent the portion from chemically bonding to and reacting with the surrounding matrix.
Claim 16
Dependent Claim
47 words
The method of claim 11 wherein the maximum lateral dimension of the protrusions is between 1.5 to 6 times the minimum lateral dimension of the members and the protrusions are separated on each said member at distances of from 3 to 15 times the maximum lateral dimension.
Claim 17
Dependent Claim
61 words
The method of claim 11 including independently controlling the shape, size, and position of the protrusions formed on one member relative to those of similar protrusions on neighboring members so that the protrusions are substantially of similar shape and equal size and equally spaced on each member; but zigzag from one member toward its neighboring members along a longitudinal direction thereof.
Claim 18
Dependent Claim
25 words
The method of claim 16 wherein the distance between two nearest protrusions on neighboring members is between 3 to 10 times the maximum lateral dimension.
Claim 19
Independent Claim
128 words
The method for increasing mechanical interaction and load transfer ability between elongated, high-strength and high-modulus reinforcing members surrounded by a strain-hardenable metal matrix in a composite, comprising, dispersing in the matrix the members in a generally parallel, spatial relationship relative to one another; effectively bonding the members to the surrounding matrix at selected, discrete surface regions along their lengths, and stressing the composite sufficiently to locally strain the matrix near the discrete regions whereby the matrix in the space between the members is substantially and selectively though nonuniformly strain-hardened and strengthened and whereby spheres of influence induced by the straining and strain-hardening in the matrix within the space near the discrete regions on one member are caused to significantly overlap similar spheres of influence near the neighboring members.
Claim 20
Independent Claim
128 words
The method for increasing mechanical interaction and load transfer ability between elongated, high-strength and high-modulus reinforcing members surrounded by a strain-hardenable metal matrix in a composite, comprising, dispersing in the matrix the members in a generally parallel, spatial relationship relative to one another; effectively bonding the members to the surrounding matrix at selected, discrete surface regions along their lengths, and stressing the composite sufficiently to locally strain the matrix near the discrete regions whereby the matrix in the space between the members is substantially and selectively though nonuniformly strain-hardened and strengthened and whereby spheres of influence induced by the straining and strain-hardening in the matrix within the space near the discrete regions on one member are caused to significantly overlap similar spheres of influence near the neighboring members.
Claim 21
Dependent Claim
46 words
The method of claim 1 wherein the dispersing step comprises orienting the members generally in the direction of the intended principal tensile loading on the composite when in use, and the stressing step comprises subjecting the composite to an external load in substantially the same direction.
Claim 22
Dependent Claim
49 words
The method of claim 1 including adjusting the volume percentage of the reinforcing members in the composite relative to the ultimate tensile strengths of the matrix and of the reinforcing members to insure substantially equal failure rates in the members and in the matrix thereby achieving optimal composite strength.
Claim 23
Dependent Claim
30 words
The method of claim 1 wherein the preparing step comprises forming discontinuous reinforcing members and the dispersing step comprises aligning the discontinuous members to within 3* relative to one another.
Claim 24
Dependent Claim
47 words
The method of claim 1 wherein the matrix is selected from the group consisting of aluminum, magnesium, titanium, beryllium, iron, copper, silver, molybdenum, and nickel; and the reinforcing members are selected from the group consisting of boron, beryllium, graphite, sapphire, silicon carbide, boron carbide, and stainless steel.
Claim 25
Dependent Claim
29 words
The method of claim 1 wherein at least one of the preparing and dispersing steps is done with the members in vertical positions to eliminate gravity-induced, processing non-uniformity results.
Claim 26
Dependent Claim
38 words
The method of claim 1 wherein the preparing step includes applying a metallic cushioning layer of substantial thickness to the surface of the members to Increase the resistance of the members to transverse and dynamic stresses and strains.
Claim 27
Dependent Claim
29 words
The method of claim 1 including mechanically working the composite to achieve at least 40 percent of the allowable straining and strain-hardening in the matrix without the failure thereof.
Claim 28
Dependent Claim
49 words
The method of claim 25 wherein the mechanical working step is done at a rate sufficiently fast relative to the heat dissipation rate in the composite so that substantial chemical bonding occurs from the relatively confined heat generated from the plastic deformation of the matrix through the mechanical work.
Claim 29
Dependent Claim
24 words
The method of claim 6 including periodically varying the growth conditions so as to form protrusions periodically along the length of the reinforcing members.
Claim 30
Dependent Claim
39 words
The method of claim 27 including adding to the melt a bond-modifying, melt-segregatable chemical; and causing the chemical to segregate periodically onto preselected surface portions of the reinforcing members in response to the periodical variations in the growth conditions.
Claim 31
Dependent Claim
39 words
The method of claim 18 wherein the effective bonding is done by chemical means and including forming controlled and uniformly shaped, substantially strain-hardened zones of continually increasing strain intensity toward the chemically bonded, discrete surface regions on the members.
Claim 32
Dependent Claim
26 words
The method of claim 18 wherein the reinforcing members are discontinuous members and the dispersing step includes aligning the members to within 3* of one another.
Claim 33
Dependent Claim
58 words
The method of claim 18 including forming substantial lateral protrusions on the members to provide bearing areas thereat so that the load transfer between the members is not limited to interfacial shears that tend to break the matrix-member interfacial bonds, but is also through the much stronger compression of the matrix pressing against the protrusions on the members.
Claim 34
Dependent Claim
24 words
The method of claim 31 wherein the bonding step comprises limiting the chemical bonding of the matrix to only the protrusions on the members.
Claim 35
Dependent Claim
36 words
The method of claim 31 wherein the forming and dispersing steps comprise zigzagging the formed protrusions from one member to its immediate neighbors, and including oppositely compressing and shearing the zigzagged protrusions on the nearby members.
Claim 36
Dependent Claim
53 words
The method of claim 18 wherein the stressing step comprises gradually and increasingly strain-hardening the matrix at the individual discrete regions, and causing selective matrix yielding away from the discrete regions to self-regulate the stress distribution until all the discrete regions are assuming substantially equal shares of the external load on the composite.
Claim 37
Independent Claim
187 words
The method for reducing mismatch stresses and strains between elongated, high-strength and high-modulus reinforcing members and the surrounding metal matrix in a composite of the type wherein the matrix is strain-hardenable and the reinforcing members substantially mismatch the matrix in thermophysical properties, comprising: dispersing in the matrix the reinforcing members according to a prespecified, regular and symmetrical geometrical pattern so as to have substantially uniform spacing between the members and to orient the members generally in the direction of the intended principle tensile loading on the composite when in use; effectively chemically bonding the matrix to selected surface regions of the members along the lengths thereof but imperfectly chemically bonding the matrix to the regions intermediate these selected regions, the selected regions zigzagging from one member to its neighbors along the direction; and stressing the composite in the direction sufficiently to develop controlled and uniformly shaped, substantially strain-hardened zones of continually increasing strain intensity toward the selected regions yet to leave the matrix between the strain-hardened zones in relatively soft and less strained conditions to allow therein substantial matrix yielding for the absorption of the mismatch stresses.
Claim 38
Independent Claim
187 words
The method for reducing mismatch stresses and strains between elongated, high-strength and high-modulus reinforcing members and the surrounding metal matrix in a composite of the type wherein the matrix is strain-hardenable and the reinforcing members substantially mismatch the matrix in thermophysical properties, comprising: dispersing in the matrix the reinforcing members according to a prespecified, regular and symmetrical geometrical pattern so as to have substantially uniform spacing between the members and to orient the members generally in the direction of the intended principle tensile loading on the composite when in use; effectively chemically bonding the matrix to selected surface regions of the members along the lengths thereof but imperfectly chemically bonding the matrix to the regions intermediate these selected regions, the selected regions zigzagging from one member to its neighbors along the direction; and stressing the composite in the direction sufficiently to develop controlled and uniformly shaped, substantially strain-hardened zones of continually increasing strain intensity toward the selected regions yet to leave the matrix between the strain-hardened zones in relatively soft and less strained conditions to allow therein substantial matrix yielding for the absorption of the mismatch stresses.
Claim 39
Dependent Claim
30 words
The method of claim 35 wherein the reinforcing members are fibers and the geometrical pattern consists of a hexagonal arrangement in which each fiber has six equally distant, closest neighbors.
Claim 40
Dependent Claim
25 words
The method of claim 35 wherein the members are discontinuous members and the dispersing step includes aligning the members to within 3* of one another.
Claim 41
Dependent Claim
19 words
The method of claim 35 including forming protrusions on the members and centering the selected regions on the protrusions.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |