US3359083A - Composite structural metal members with improved fracture toughness - Google Patents

Composite structural metal members with improved fracture toughness Download PDF

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US3359083A
US3359083A US463973A US46397365A US3359083A US 3359083 A US3359083 A US 3359083A US 463973 A US463973 A US 463973A US 46397365 A US46397365 A US 46397365A US 3359083 A US3359083 A US 3359083A
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fracture toughness
thickness
laminar
laminae
sheets
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Herbert L Leichter
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C14/00—Alloys based on titanium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550 degrees C
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550 degrees C
    • B23K35/3006—Ag as the principal constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/01—Layered products comprising a layer of metal all layers being exclusively metallic
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C16/00—Alloys based on zirconium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C5/00—Alloys based on noble metals
    • C22C5/06—Alloys based on silver
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C5/00—Alloys based on noble metals
    • C22C5/06—Alloys based on silver
    • C22C5/08—Alloys based on silver with copper as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/922—Static electricity metal bleed-off metallic stock
    • Y10S428/923—Physical dimension
    • Y10S428/924—Composite
    • Y10S428/926—Thickness of individual layer specified
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/922—Static electricity metal bleed-off metallic stock
    • Y10S428/9335—Product by special process
    • Y10S428/939—Molten or fused coating
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12632—Four or more distinct components with alternate recurrence of each type component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12896—Ag-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12903—Cu-base component
    • Y10T428/12917—Next to Fe-base component
    • Y10T428/12924—Fe-base has 0.01-1.7% carbon [i.e., steel]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12951—Fe-base component
    • Y10T428/12972—Containing 0.01-1.7% carbon [i.e., steel]

Definitions

  • HERBERT L. LE/CHTER ATTORNEY United States Patent 3,359,083 COMPOSITE STRUCTURAL METAL MEMBERS WITH IMPROVED FRACTURE TOUGHNESS Herbert L.chter, Castro Valley, Califi, assignor to the United States of America as represented by the United States Atomic Energy Commission Filed June 14, 1965, Ser. No. 463,973 8 Claims. (Cl.
  • ABSTRACT OF THE DISCLOSURE High fracture toughness laminate comprised of superposed sheets of metal joined together, each sheet having a thickness which is substantially equal to that at which the fracture toughness of the specific material of which the sheet is made is at a maximum.
  • the present invention relates to laminar structural materials, and more particularly to laminates having a predetermined laminar thickness to optimize the fracture toughness thereof.
  • the fracture toughness of a material is a quantity which is related to the force necessary to induce growth of a fracture or flaw to such an extent that failure of the material structure occurs.
  • the stresses necessary to produce failure in structural materials having flaws, cracks, or similar imperfections are generally considerably less than the inherent ultimate or yield strength of the material.
  • the present invention provides a laminar structural material which exhibits enhanced fracture toughness and which is, therefore, highly resistant to failure due to crack propagation at stresses below the inherent or ultimate yield strength.
  • the present laminar material is comprised of a multiplicity of joined laminae, the thickness of each preferably being selected to be near the thickness at which the fracture toughness is at a maximum and the selected laminae are then bonded to provide a composite structure in which the fracture or stress failure resistance of the composite structure is optimized.
  • the fracture toughness of a material may be characterized by the expression where E is the modulus of elasticity of the material, 1r is the universal constant for a circle, and G represents the stored elastic strain energy which is released as a crack of length a advances over an additional unit area of the material if the material is under the influence of a stress 0' normal to the plane of the crack. In the limit, G approaches a critical value G, which is defined as the release of an amount of energy which in response to the loading of the material leads to immediate failure by rapid crack propagation. This value is commonly known as the fracture toughness of the material.
  • the fracture toughness of a material appears to be a basic material property, and is a function of a number of variables, in particular the structure and composition of the material, the temperature of the material, the rate of loading, and the dimensions of the material.
  • the fracture toughness of cer- 3,359,083 Patented Dec. 19, 1967 tain laminar materials has been found to be a function of the thickness dimensions of a homogeneous specimen of material in which a crack may be located. Further, it has been discovered that the functional relation between fracture toughness and the thickness of materials exhibit a maximum over readily ascertainable thickness ranges. In the case of metals, it has been confirmed by experimental testing that the maximum generally occurs at a thickness of less than about 0.2 inch and down to about 0.01 inch. Moreover, it has been found that sheet or laminar materials, e.g.
  • metal sheet having a thickness dimension near that at which fracture toughness is a maximum can be bonded in intimate laminar relationship to yield a composite structural body having a fracture toughness which greatly exceeds what might be expected.
  • laminar or sheet materials should exhibit a maximum fracture toughness related to thickness is not completely apparent. It is possible that the method used to produce the sheet material, e.g. rolling or other mechanical working with intervening heat treatment which necessarily varies with the thickness of the sheet being formed yields a metallographic structure at certain thicknesses connoting a particular treatment which yields a metallurgical structure of optional properties. Moreover, minute or incipient fracture defects may have a minimum occurrence in said range.
  • the present invention provides a laminar body of improved fracture toughness due to the controlled laminar thickness. It should be understood that the improvement in fracture toughness can be achieved for materials having isotropic as well as anisotropic characteristics, whether the orientation of the material in successive layers is identical or in different directions. Accordingly, the present material may be thought of as being in the nature of a continuous structural body, which is a composite of laminae of selected thickness dimensions related to a maximum in the fracture toughness characteristic curve joined or bonded in face to face laminar relation to provide a composite structural member of exceptional fracture toughness.
  • the fracture toughness of a material has been shown to be a quantity which is extremely important in practical engineering work.
  • many structural materials are likely to have flaws or cracks as a consequence of which structural failure is likely to occur due to crack propagation at loads considerably and unpredictably less that the ultimate strength of a material as determined from tests of a near perfect specimen.
  • structures are usually designed with relatively large safety factors.
  • structural materials are generally tested and inspected to locate cracks and flaws by procedures which are time-consuming and costly. Thereafter, appropriate remedial action may be taken, such as welding, or even discarding the member entirely at considerable economic loss.
  • the laminate of the present invention is ideally suited by virtue of its improved fracture toughness characteristics.
  • FIGURE 1 is a graph of the fracture toughness of various metals as related to the thickness of the material.
  • FIGURE 2a is an isometric drawing of a laminated structural test specimen which is notched and fatigue cracked across the face of the top lamina.
  • FIGURE 2b is an isometric drawing of a laminated structural test specimen which is notched and fatigue cracked through-the-thickness perpendicular to the plane of the laminae.
  • the present invention is a composite laminated structural material formed of bonded laminar or sheet materials which is characterized by the property that its fracture toughness varies with the thickness of the material and exhibits a maximum.
  • the laminate is comprised of a multiplicity of individual laminar layers, the thickness of each being selected at or near the thickness corresponding to the maximum fracture toughness.
  • the laminar layers are joined together in face to face relation into an integral body having the overall dimensions of a desired structural member.
  • the present laminates are used in the manufacture of structural beam members or plate, the total thickness of which exceeds the optimum fracture toughness of the material by at least a factor of about two.
  • the failure resistance of a structural material is increased whenever the weighted average of the fracture toughness of the individual laminae exceeds the fracture toughness of a continuous homogeneous body of the same material as said laminae. Due to the properties of the composite laminar structure the toughness properties of structural bodies fabricated in this manner are with great reliability in excess of the equivalent unlaminated conventional structures while other advantages, e.g. reduced weight can often be attained since a considerably reduced safety margin can be reliably used.
  • the laminae of appropriate shape may be joined by any bonding method, including adhesive and brazing or by mechanical means, such as spotwelding, riveting, or parts may be punched from laminates, in some instances.
  • the laminae preferably are joined in face to face relation by using an appropriate bonding medium to render an integral or unitary body where the bond between the laminae extends uniformly over the entire faces of the laminae. Forces exerted on such a body, e.g. shear stresses, etc., are thereby transmitted between the laminae and evenly distributed over the entire structural member to provide bodies of high flexural modulus, strength, etc., while simultaneously obtaining the greatly enhanced fracture toughness.
  • FIGURE 1 graphs are presented illustrating the fracture toughness-thickness relation of two alloys.
  • the graph labelled (a) is for a titanium alloy, specifically Ti-5Al-2.5Sn, and the graph designated (b) is for grade 300, 18% Ni maraging steel. Both of these curves are seen to exhibit a maximum fracture toughness in the thickness region between 0.025 and 0.1 inch.
  • the fracture toughness decreases with increasing thickness of the sheet or member and asymptotically approaches a constant value.
  • the fracture toughness of a continuous homogeneous material is equal to the fracture toughness corresponding to its thickness as given by the graph.
  • the fracture toughness of a laminate is deter-mined in large measure by the selected thickness of individual laminae providing toughness of the individual laminae, and further by the combination of selected laminae to provide a composite structural body. If the individual laminae have a thickness equal to the thickness at which the fracture toughness of the material is a maximum, the laminate comprised of such laminae will have a fracture toughness which is significantly superior to any continuous homogeneous body of equal or even greater total thickness constructed of the same material.
  • Tests performed at slow strain rates are the Center-Notch Tensile Test and the Slow-Bend Prenotched Charpy Method. These methods are described in detail in the following references: American Society for Testing Material (ASTM) Committee Reports on Fracture Testing of High Strength Metallic Materials, ASTM Bulletin, January and February 1960; and Sheet Fracture Toughness Evaluation by Impact and Slow Bend, G. M. Orner and C. E. Hartbower, Welding Journal, Research Supplement, September 1961.
  • Another method for determining the fracture toughness of materials is the Prenotched Charpy Impact test, which is carried out at high strain rates of about 10 in./in. sec. This test has limitations the values obtained for very tough materials are generally low. While measuring absolute fracture toughness values is somewhat subject to error, the Prenotched Charpy Impact Test yields a fracture toughness-thickness curve with a reliable shape and relative values. However, for present purposes the primary purpose is to determine the material thickness at which the fracture toughness is a maximum and to obtain a knowledge of the relative increase of the fracture toughness which can be achieved by a laminate over a continuous homogeneous body.
  • the fracture toughness is defined as the energy absorbed in fracturing the specimen, divided by the area of the fracture. This value is determined for a number of specimens of varying thicknesses and plotted. A smooth curve joining the individual measurements will then result in a graph as illustrated in FIGURE 1.
  • the fracture toughness of the material having a thickness in this range substantially exceeds the fracture toughness values G which the curve approaches.
  • the region of enhanced fracture toughness is defined as extending between the thickness values at which the fracture toughness is intermediate between the maximum fracture toughness and G
  • FIGURES 2a and 21 there are shown laminated structural beams constructed in accordance with the present invention.
  • Individual laminae 11 are joined together in face to face relationship.
  • the thickness d of each lamina corresponds to the thickness of the sheet material under the elevated portion of the fracture toughness curve shown in FIG. 1.
  • the joints 12 are formed most commonly and preferably by a layer of metallic bonding or joining alloy, e.g. brazing material fused to the faces of adjacent laminae 1 1.
  • the bond formed between the braze material and the laminae 11 extends continuously over the entire face of the laminae.
  • the braze material is selected in accord with usual engineering practice on the basis of the quality of the bond which the braze forms with the lamina material, and on the basis of its physical properties which must be commensurate with the environmental demands on the laminate. While the preferred method of bonding the laminae 11 is brazing, which will be taken to include all appropriate methods using a bonding alloy or a diffusion bonding agent, e.g., silver, it will be realized, that when the environmental conditions permit their use, other joining methods maybe used in place of brazes, provided that a firm bond is formed between the laminae 11. Thus, in low temperature applications requiring only moderate bonds strength, synthetic adhesives such as catalyzed epoxy adhesive resins can be used to join laminae 11. With brazing or diffusion bonding, the present laminates are constructed by heating a. pressurized stack of alternate layers of brazing foil and laminar plates to the brazing temperature of the foil, preferably in an inert atmosphere.
  • a preferred method of making the laminate is by the Hortonclad process, described in detail in US. Patent No. 2,713,196 issued to R. L. Brown on July 19, 1955.
  • material sheets are stacked with braze alloy in foil form interposed between the sheets.
  • This stack of alternating laminar material and braze alloy foil is sealed in a flexible steel envelope, placed under a vacuum, and heated to the brazing temperature and held at this temperature for a specified period depending on the brazing material.
  • a preferred method to carry out the brazing step is to dispose the stack of laminar material and interposed braze foil in a stainless steel envelope.
  • This envelope is hermetically sealed and adapted for evacuation. Prior to disposing the stack in a furnace, the envelope is evacuated to a pressure of the order of microns. The stainless steel envelope collapses and compresses the stack, while excluding most of the air from the stack during the heating step. The envelope is then heated to and held at the brazing temperature in a furnace for a specified period.
  • the composite laminate of the invention and manufacturing method will be further illustrated in the following specific examples.
  • the stack was placed into a stainless steel envelope and compressed by evacuating the envelope to about microns.
  • the envelope was placed into a furnace and the composite was heated to a temperature of 1727:2 F. This temperature and the pressure of 150 microns were maintained for a period of about 5 minutes to produce a brazing joint between the titanium alloy laminae. Thereafter the envelope containing the laminate was air cooled under vacuum. The integrity of the bonds between the laminae was checked for defects by ultrasonic methods.
  • Charpy specimens were cut from the laminated plate, notched and fatigue precracked to a depth of about 0.03" and the properties tested by the Prenotched Charpy Impact Test described above. With reference to FIG. 2a, one type of specimen was notched across the face 13 of the top layer normal to the plane of the lamina. A second type of specimen, illustrated in FIG. 2b was notched across the sides 14 and a through-the-thickness fatigue crack introduced at the bottom of the V-shaped notch. The physical properties of both laminar specimens and identical specimens of a continuous forged bar were tested under the same conditions. The laminates which were notched and cracked across the face of the top layer could not be completely broken at the maximum impact loading of 240 ft. lbs. delivered by the pendular hammer of the testing machine. The results of the tests with the through-the-thickness cracked specimen and the continuous bar are given in Table 1.
  • a six-ply laminated plate of grade 250 18% nickel maraging steel was made by assembling a stack of 6 steel laminae of a thickness of 0.062 inch.
  • a 2.0 mil thick braze alloy foil having a composition of 92% silver, 7.5% copper and 0.5% lithium was placed between successive steel sheets.
  • the assembly was disposed into a flexible steel envelope, placed into a furnace and heated to a brazing temperature of 17551-5 F. for a period of 10 minutes, while maintaining the vacuum at about 40 microns.
  • the laminate was then air cooled and reheated to the anstenitizing temperature of 1500 F.
  • Notched Charpy structural members were prepared from the laminate and from homogeneous maraging steel bar stock and tested as outlined above. The results are also given in Table I. Again the specimens notched across the face of the top layer exceeded the 240 ft. lb. capacity of the testing equipment. Rough calculation based on the partially fractured specimens indicated a fracture toughness between about 30 and 40 times as great as the fracture toughness of the continuous bar.
  • the data in- Table I illustrates the improvement in the fracture toughness of the laminated materials over the continuous homogeneous bar materials. Although only two specific examples have been given, it is not intended to convey that the invention be limited to these specific materials.
  • the remarkable improvement of the fracture toughness characteristic of these laminates over homogeneous bodies of the same dimensions can be analogously achieved in other materials, provided only that the fracture toughness-thickness curve for the material exhibit a maximum and that a suitable binder be employed to join together the laminar composite.
  • the optimum or maximum effects are generally obtained using a laminate comprised only of metal sheets having the specified maximum fracture resistant thicknesses improvement is obtained if even a single such sheet is used with other thickness sheets and with sheets of other materials laminated therewith.
  • the additional benefits obtained in the composite structure generally requires that two or more such sheets or laminae be used. Therefore, the scope of the invention is to be limited only by the following claims.
  • a composite structural body of improved fracture toughness comprising: a plurality of laminar sheets of a titanium alloy consisting essentially of 92.5% by weight of titanium, 5% by weight of aluminum and 2.5% by weight of tin, a combined thickness substantially greater than the thickness range in which the fracture toughness of a homogeneous body of said alloy is at an optimum, said sheets having a thickness in the range of 0.02 and 00.2 inch wherein the sheets individually exhibit an optimum fracture toughness, said laminar sheets being disposed in contiguous face-to-face relation, bonding means joining said laminar sheets in said contiguous face-to-face relation to provide a structural body of improved fracture toughness.
  • said sheets individually having a thickness in the range of about 0.01 to 0.15 inch wherein said steel exhibits an enhanced fracture toughness, said laminar sheets being disposed in contiguous face-to-face relation and bonding means joining said laminar sheets in said contiguous face-to-face relation to provide a structural body of improved fracture toughness.
  • bonding means is a bonding agent layer disposed between and fused to adjacent faces of said laminar sheets.
  • the laminate of claim 1 further defined in that said titanium alloy laminar sheets have a thickness in the range of about 0.03 and 0.13 inch.
  • said bonding agent layer is a brazing alloy consisting of 92% by wt. of silver, 7.5% by wt. of copper, and 0.5% by wt. of lithium.
  • braze joint layer is comprised of a brazing alloy consisting of 63% by wt. of copper, 22% by wt. of manganese, 10% by wt. of cobalt and 5% by wt. of nickel.

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  • Engineering & Computer Science (AREA)
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  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
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US463973A 1965-06-14 1965-06-14 Composite structural metal members with improved fracture toughness Expired - Lifetime US3359083A (en)

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US463973A US3359083A (en) 1965-06-14 1965-06-14 Composite structural metal members with improved fracture toughness
GB22521/66A GB1145575A (en) 1965-06-14 1966-05-20 A metallic laminate of enhanced fracture toughness
DE19661521568 DE1521568A1 (de) 1965-06-14 1966-06-11 Mehrschichten-Bauteil
FR65303A FR1513255A (fr) 1965-06-14 1966-06-13 Elément de structure à résistance améliorée à la fissuration
BE682505D BE682505A (fr) 1965-06-14 1966-06-14

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3849079A (en) * 1969-12-19 1974-11-19 Anvar Metallic materials based on martensitic steel
CN102009284A (zh) * 2010-11-04 2011-04-13 西安航空动力股份有限公司 一种用于高温合金与白铜焊接的钎料及其制备方法
US9914282B2 (en) 2014-09-05 2018-03-13 United Technologies Corporation Composite material with controlled fracture regions
CN109933925A (zh) * 2019-03-19 2019-06-25 首钢集团有限公司 一种金属板材的冲压成形性能预测方法
CN114273816A (zh) * 2022-01-13 2022-04-05 郑州机械研究所有限公司 一种钎料及其制备方法
CN115003499A (zh) * 2020-01-24 2022-09-02 住友化学株式会社 光学层叠体和显示装置

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CN111508572B (zh) * 2020-04-16 2023-04-14 中国飞机强度研究所 一种金属材料平面应力断裂韧度的确定方法

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US1005142A (en) * 1910-07-26 1911-10-10 Robert C Becker Composite steel bar.
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US2713196A (en) * 1953-03-17 1955-07-19 Chicago Bridge & Iron Co Method for cladding and product resulting therefrom
US2767467A (en) * 1951-02-02 1956-10-23 Metals & Controls Corp Solid phase bonding of metal strips
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US125245A (en) * 1872-04-02 Improvement in the manufacture of iron
US365300A (en) * 1887-06-21 John faebel
US1005142A (en) * 1910-07-26 1911-10-10 Robert C Becker Composite steel bar.
US1087561A (en) * 1911-07-01 1914-02-17 Lewis B Tebbetts Printing-plate.
US2438759A (en) * 1941-05-21 1948-03-30 Liebowitz Benjamin Manufacture of composite steel plates
US2767467A (en) * 1951-02-02 1956-10-23 Metals & Controls Corp Solid phase bonding of metal strips
US2713196A (en) * 1953-03-17 1955-07-19 Chicago Bridge & Iron Co Method for cladding and product resulting therefrom
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US3849079A (en) * 1969-12-19 1974-11-19 Anvar Metallic materials based on martensitic steel
CN102009284A (zh) * 2010-11-04 2011-04-13 西安航空动力股份有限公司 一种用于高温合金与白铜焊接的钎料及其制备方法
US9914282B2 (en) 2014-09-05 2018-03-13 United Technologies Corporation Composite material with controlled fracture regions
CN109933925A (zh) * 2019-03-19 2019-06-25 首钢集团有限公司 一种金属板材的冲压成形性能预测方法
CN109933925B (zh) * 2019-03-19 2023-08-15 首钢集团有限公司 一种金属板材的冲压成形性能预测方法
CN115003499A (zh) * 2020-01-24 2022-09-02 住友化学株式会社 光学层叠体和显示装置
CN114273816A (zh) * 2022-01-13 2022-04-05 郑州机械研究所有限公司 一种钎料及其制备方法
CN114273816B (zh) * 2022-01-13 2023-12-01 郑州机械研究所有限公司 一种钎料及其制备方法

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BE682505A (fr) 1966-11-14
DE1521568A1 (de) 1969-09-11
FR1513255A (fr) 1968-02-16
GB1145575A (en) 1969-03-19

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