Abstract: An outwardly grown diffusion aluminide bondcoat is formed on a superalloy substrate and has higher concentrations of Al and Pt and lower concentrations of harmful impurities (e.g. Mo, W, Cr, Ta, S, etc.) at an outermost region of the bondcoat than at an innermost region thereof adjacent the substrate. The bondcoat is pretreated prior to deposition of a ceramic thermal insulative layer in a manner that reduces grain boundary ridges on the outermost bondcoat surface without adversely affecting the outermost region thereof, and then is heat treated to thermally grow a stable alpha alumina layer on the bondcoat prior to deposition of a ceramic layer.

Abstract: The present invention relates to composite electroless coatings with varying densities of codeposited particles in the plated layer along the surface of the substrate where said variation of densities is directed by the angle of rotation of the substrate during the coating process.

Abstract: In an electrodeposited hard-chromium coat, particularly for a piston ring, which is substantially formed of an electrolyte containing hexavalent chromium, wherein there are cracks in the coat and diamond particles are embedded in these cracks, the diamond particles have a size ranging from 0.25 to 0.5 &mgr;m.

Abstract: A metallurgical product, such as brazing sheet, comprises a core, on at least one side of the core an interlayer bonded to the core and a cladding bonded to the interlayer. The core and the interlayer are a compositely cast material having at their mutual interface a bond formed in a casting process by their simultaneous solidification from contacting melts of their respective materials. This provides a simple process, with good adhesion. The cladding is applied subsequently and the composite material is rolled into a sheet or plate product.

Abstract: The coating plant includes a device for running a sheet to be coated along a traveling path past a window for the evaporation or sublimation of elements A an B, sources for the evaporation or sublimation of elements A and element B placed successively in a direction parallel to the traveling path so as to emit elements A and B through the window and a screen for reducing the angle of emission from the source of element B below the limit represented by an exit edge of the window, the screen being mounted so as to move translationally perpendicular to the traveling path and to move along the traveling path between the source of element A and the source of element B so as to obtain either a —A—AB—A— or a —B—AB—B—coating.

Abstract: An anti-stick coating that inhibits the adhesion of contaminants that form deposits on the internal cooling passages of gas turbine engine components. The anti-stick coating is formed as an outer coating of the internal cooling passages, and preferably overlies an environmental coating such as a diffusion aluminide coating formed on the passage surfaces. The outer coating has a thickness of not greater than three micrometers, and is resistant to adhesion by dirt contaminants as a result of comprising at least one layer of tantala, titania, hafnia, niobium oxide, yttria, silica and/or alumina. The outer coating is preferably deposited directly on the environmental coating by chemical vapor deposition.

Abstract: A thermal barrier coating for superalloy articles such as turbine engine vanes and blades that are exposed to high temperature gas is disclosed. The coating includes a columnar grained ceramic layer applied to an aluminide or MCrAlY bond coat by electron beam physical vapor deposition. The ceramic layer is comprised a plurality of layers of zirconia stabilized with 20 percent yttria and the interfaces between the layers are decorated with particles selected from a group consisting of Ta2O5 and alumina. Though not essential to the invention a layer of tetragonal zirconia may be deposited both under and over the ceramic coat. An improved electron physical beam vapor deposition process for applying this ceramic layer is also disclosed.

Abstract: A functional film includes a transition layer having a first constituent having SiO as a dielectric material and at least one second constituent selected from aluminum (Al), silver (Ag), silicon (Si), germanium (Ge), yttrium (Y), zinc (Zn), zirconium (Zr), tungsten (W) and tantalum (Ta). The first and second constituents have corresponding gradual content gradients according to a thickness of the functional film.

Abstract: Coating for high temperature gas turbine components that include a MCrAlX phase, and an aluminum-rich phase, significantly increase oxidation and cracking resistance of the components, thereby increasing their useful life and reducing operating costs. The aluminum-rich phase includes aluminum at a higher concentration than aluminum concentration in the MCrAlX alloy, and an aluminum diffusion-retarding composition, which may include cobalt, nickel, yttrium, zirconium, niobium, molybdenum, rhodium, cadmium, indium, cerium, iron, chromium, tantalum, silicon, boron, carbon, titanium, tungsten, rhenium, platinum, and combinations thereof, and particularly nickel and/or rhenium. The aluminum-rich phase may be derived from a particulate aluminum composite that has a core comprising aluminum and a shell comprising the aluminum diffusion-retarding composition.

Abstract: This invention is related to a metal-based gradient composite material having good lubrication and wear-resistance properties. The composite material comprises a metal (M) matrix and a gradient composite layer of metal sulfide (M[S]) and metal oxide,(M[O]) on the surface of said metal matrix. In the gradient composite layer,, the sum (Ds+Do) of the concentration of metal sulfide (Ds) and the concentration of metal oxide (Do) decreases gradually from the surface to the interior, and the concentration of metal (DM) increases from the surface to the interior. The invention is also related to a process for producing the gradient composite material and the use of the same.

Abstract: An aluminum alloy plate for an automobile has a chemical composition containing 0.8 to 1.5% by mass of Si, 0.4 to 0.7% by mass of Mg and 0.5 to 0.8% by mass of Cu. The crystal grain size is 10 to 40 &mgr;m. Cu content obtained by analyzing the outermost surface of the aluminum alloy with an oxide film according to X-ray photoelectron spectroscopy (XPS) is {fraction (1/10)} to ½ of the Cu content of the bulk of the aluminum alloy plate.

Abstract: A coating system and method for forming the coating system on an article designed for use in a hostile environment, such as the superalloy turbine, combustor and augmentor components of a gas turbine engine. The method employs a nitrided zone in the surface of the superalloy substrate to inhibit the formation of deleterious topologically-close packed (TCP) phases in the substrate when protected by an aluminum-rich coating and optionally a thermal insulating ceramic layer. Superalloys of particular interest are those containing significant levels of TCP phase-forming elements, such as tungsten, rhenium, tantalum, molybdenum and chromium.

Abstract: An environmentally resistant coating comprising silicon, titanium, chromium, and a balance of niobium and molybdenum for turbine components formed from molybdenum silicide-based composites. The turbine component may further include a thermal barrier coating disposed upon an outer surface of the environmentally resistant coating comprising zirconia, stabilized zirconia, zircon, mullite, and combinations thereof. The molybdenum silicide-based composite turbine component coated with the environmentally resistant coating and thermal barrier coating is resistant to oxidation at temperatures in the range from about 2000° F. to about 2600° F. and to pesting at temperatures in the range from about 1000° F. to about 1800° F.

Abstract: A continuous steel strip consisting especially of austenitic or martensitic steel, with at least one weld seam running crosswise to the longitudinal extension of the steel strip, for twin presses. The steel strip includes at least one first surface layer which extends essentially across the entire steel strip and which has a different composition to an intermediate layer located between said first surface and a second surface facing the first. The intermediate layer extends essentially across the entire steel strip. The first surface layer consists of the steel of the steel strip and has regularly positioned heat-influenced areas, e.g., zones, situated next to or overlapping each other and/or fusion penetration areas, e.g., zones.

Abstract: The invention relates to a method and a device for the production of a strip-like metallic composite material by the high-temperature dip coating of a metallic carrier strip, consisting of a metallurgic vessel for receiving the liquid depositing material, through which the carrier strip is capable of being led in a preferably vertical run-through direction by means of pairs of rollers arranged on the entry and the exit side, and of a preheating device for the carrier strip, said preheating device being located upstream of the metallurgic vessel. At the same time, the preheating device (41) is arranged in a housing (61) which is arranged in the entry region upstream of the metallurgic vessel (11) and surrounds the carrier strip (21) and into which the medium coming from a media supply (52) is capable of being introduced via at least one feed (51) led into the housing.

Abstract: The high tension steel sheet includes 0.1 wt % or more of silicon and has a zinc-plating layer thereon. When sputtering analysis is performed in the depth direction from the surface of the high tension steel sheet after the zinc-comprising-plating layer is removed by dissolution, a surface-concentrated Si index X defined by the formula, X=(the maximum intensity A of Si on the surface of the high tension steel sheet/the average intensity B of Si in the steel)×the content of Si in the steel sheet on a wt % basis, is 12 or less.

Abstract: A method for fabricating a reactive solder or braze includes forming a metallic matrix with an interior region and surface regions by actively providing a higher concentration of reactive atoms to the interior region than to the surface regions.

Abstract: A refractory metal intermetallic composition comprising titanium (Ti), hafnium (Hf), silicon (Si), aluminum (Al), chromium (Cr), germanium (Ge), tin (Sn), iron (Fe), and a balance of niobium (Nb) for use in composite structures having applications in turbine components.

Abstract: A method of ion implantation using oxygen backfill and a modified surface layer formed therefrom are provided. The method of ion implantation includes the steps of placing a substrate metal in an ion implantation vacuum chamber, introducing oxygen into the ion implantation vacuum chamber and directing a beam of ions at the substrate metal. The modified surface includes a substrate metal and implanted atoms at a surface of the substrate metal. The implanted atoms are integrated with the substrate metal. The substrate metal has an implanted atom concentration of at least 5 atomic % to a depth of over 250 Å.

Abstract: A method of forming a plain bearing lining on a substrate, the method comprising high velocity oxy-fuel spraying particles of a bearing metal onto the substrate and treating said layer to form it into a lining.

Abstract: The invention relates to a method and apparatus for the production of protective coatings on parts. A coating formed in accordance with the invention has a chemical composition and structure gradient across its thickness. The coating is obtained by heating of a composite ingot including a body and at least one insert disposed within the body. As the composite ingot is heated it sequentially evaporates to produce a vapor with a chemical composition varying over the evaporation time period. The composition of the body and composition and location of the insert within the body function to determine the chemical composition of the vapor at any time. Condensation and/or deposition of the vapor onto a substrate forms the inventive coating.

Abstract: A plated material for connectors, having superior insertion and withdrawal properties, comprises an intermediate layer consisting of Ni alloy plating having a Vickers hardness of 450 to 750 Hv and a thickness of 0.3 to 2 &mgr;m provided on a base metal consisting of Cu or Cu alloy, a reflowed Sn or Sn alloy plated surface layer provided thereon, and an alloy layer consisting primarily of Sn—Ni and having a thickness of 0.05 to 2 &mgr;m formed by diffusion between the intermediate layer and the surface layer, in which average grain size of said Sn—Ni compound is 0.05 to 1 &mgr;m.

Abstract: A method for coating stainless steel in which a metallic material layer of Cr and alloys of Cr and at least one of Mo, W, Ni, Si, Ti, Zr is deposited onto a metal substrate. The metallic material layer is then annealed so as to form a diffusion layer between the metallic protective coating and the metal substrate. Thereafter, the metallic material layer may be passivated, forming a stable composition of at least one of carbides, borides, nitrides, silicides, oxides, and mixtures thereof on the metallic protective coating. The protective coatings of this invention significantly reduce the corrosion rate of stainless steel used in bromide-based absorption systems.

Abstract: Composite wear component produced by casting and consisting of a metal matrix whose working face or faces include inserts which have a very high wear resistance, characterized in that the inserts consist of a ceramic pad, this ceramic pad consisting of a homogeneous solid solution of 20 to 80% of A12O3 and 80 to 20% of ZrO2, the percentages being expressed by weights of the constituents, and the pad then being impregnated with a liquid metal during the casting.

Abstract: A slide member is made of an aluminum alloy and compositely reinforced at its sliding surface by a reinforcing material. The reinforcing material is a mixture of alumina short fibers consisting of not less than 80 wt. % alumina and the remainder silica and having 5-60 wt. % alpha alumina content, and non-spherical mullite particles consisting of 40-86 wt. % alumina and the remainder silica and having 3-60 microns mean diameter. The volumetric percentages of the alumina short fibers and the mullite particles are 2-12% and 5-25%, respectively, on the basis of the volume of the reinforced portion.

Abstract: Processes for preparing copper-INVAR-copper (CIC) for use in making chip packaging and the CIC created. One process comprises annealing a CIC section at a temperature in a range of 1475° F. to 1625° F. for a time in a range of 40 to 120 seconds. Another process includes heat treating a CIC section at a temperature in a range of 1275° F. to 1425° F. for a time in a range of 40 to 120 seconds. The above processes can be combined. The CIC section created exhibits unique electrical, physical, and mechanical properties.

Abstract: A metal article which includes a protective coating system is described. The coating system includes a braze alloy layer and a plasma-sprayed bond coat. The bond coat may lie on top of the braze alloy layer, or the braze alloy layer may lie on top of the bond coat. In the case of a porous bond coat, partial or complete densification of the bond coat is sometimes carried out. Densification is achieved by heat treating the article, so that the braze alloy material migrates into the pores of the bond coat to a selected thickness. Related processes are also described.

Abstract: An aluminum alloy plate for a planographic printing plate capable of being provided with a satisfactory roughed surface by electrolytic etching. The aluminum alloy plate contains 0.1 to 0.6% of Fe, 0.01 to 0.2% of Si, 5 to 150 ppm of Cu, and balance of Al and unavoidable impurities and has a surface layer portion formed of a metastable phase dispersion layer in which metastable phase AlFe-based intermetallic compound particles are dispersed. The metastable intermetallic compound particles each act as a starting point for pits. The alloy plate is formed with a roughed surface which is reduced in unetching and uniformly formed with pits, by electrolytic etching.

Abstract: A diffusion aluminide coating having a graded structure is applied over a nickel base superalloy substrate. The coating has an inner region of a diffusion aluminide adjacent to the substrate rich in a reactive element, typically Hf, Si or combinations of the two. The near surface region is a diffusion aluminide which is substantially free of reactive elements. Such coatings when used as bond coats in thermal barrier coating systems exhibit improved spallation performance.

Abstract: A method for forming a composite vapor-deposited film which is suitable for the deposition on the fluorescent screen of a color television picture tube and the like and in which one side has a high light-reflectance and the other side has a property of absorbing heat rays, and a composite vapor-deposition material suitable for vacuum vapor deposition therefor are disclosed. This composite vapor-deposition material has an aluminum envelope and a low vapor-pressure metal/metalloid compound powder in the its core region. It is desirable that the low vapor-pressure metal/metalloid compound powder is dispersed and retained with aluminum in the core region.

Abstract: A silicon wafer is provided having controlled distribution of defects, in which denuded zones having a sufficient depth inward from the surface of the wafer are combined with a high gettering effect in a bulk region of the wafer. In the silicon wafer, oxygen precipitates, which act as intrinsic gettering sites, show vertical distribution. The oxygen precipitate concentration profile from the top to the bottom surfaces of the wafer includes first and second peaks at first and second predetermined depths from the top and bottom surfaces of the wafer, denuded zones between the top and bottom surfaces of the wafer and each of the first and second peaks, and a concave region between the first and second peaks, which corresponds to a bulk region of the wafer. For such an oxygen precipitate concentration profile, the wafer is exposed to a rapid thermal annealing process in a gas mixture atmosphere comprising ammonia (NH3) and argon (Ar) at temperatures below about 1200° C.

Abstract: The functionally graded alloy having a composition comprising 3-10 weight % of Al, 5-20 weight % of Mn, the balance being substantially Cu and inevitable impurities has a first portion composed essentially of a &bgr;-phase, a second portion composed essentially of an &agr;-phase and a Heusler phase, and a third portion having a crystal structure changing continuously or stepwise from the first portion to the second portion. The functionally graded alloy can be produced by forming a copper-based alloy having the above composition, keeping it at 500° C. or higher and rapidly cooling it, and then subjecting it to an aging treatment by a gradient temperature heater. Such functionally graded alloy can suitably be used for guide wires and catheters.

Abstract: A rolling bearing contains no more than 0.3 wt % of nitrogen in a grinding allowance portion after carbonitriding and hardening heat treatments, contains from 0.9 wt % (inclusive) up to 1.6 wt % (inclusive) of carbon and from 0.05 wt % (inclusive) up to 0.3 wt % (inclusive) of nitrogen in the surface layer of the finished part and has a nitrogen gradient of no more than 0.5 wt %/mm in the surface layer of the finished part. The rolling bearings are improved in grinding efficiency and which have their rolling life extended significantly.

Abstract: A member is disclosed which includes a hard carbon film provided through an interlayer or directly on a main body such as a vane. A mixed layer is formed within the main body or interlayer adjacent to an outer surface of the main body or interlayer. The mixed layer contains carbon and a constituent element of either the main body or the interlayer. The mixed layer has a carbon content gradient in its thickness direction so that a carbon content in a thickness portion thereof closer to an outer surface of the mixed layer is higher than in a thickness portion thereof remoter from the outer surface of the mixed layer.

Abstract: The present invention relates to a porous electrode wire for use in electrical discharge machining and the method of manufacturing the same. The wire improves the machining speed at least 15% compared with a conventional zinc coated wire, which results from an increased cooling ability of the wire with a cooling liquid because of the increase in the surface area of the wire having porous surface morphology. Since the surface of the porous wire presents uniform profile of outer periphery rather than surface protrusions, it does not affect machining accuracy. Further, the porous nature of the wire is expected to improve flushability during the electrical discharge machining, providing spaces to eliminate particles of the machining. Therefore, in accordance with the method of the present invention, a zinc coated wire having improved performance of machining speed and flushability compared with a conventional coated wire can be provided without additional processes.

Abstract: The invention provides a method of surface hardening a titanium material wherein titanium-aluminum alloy powders or aluminum oxide powders are brought into contact with the surface of the titanium material, and a heat treatment is applied thereto, causing aluminum contained in the powders to be diffused in the surface of the titanium material so that intermetallic compounds such as Ti3Al, TiAl, and the like are formed inmediately underneath the surface of the titanium material, thereby enhancing surface hardness without causing surface exfoliation. The invention also provides a surface-hardened titanium-base material, and decorative articles and watchcases, composed of the surface-hardened titanium-base material, which are substantially impervious to scratches, and not prone to cause metallic allergy.

Abstract: The present invention aims to produce the material for a battery container having the improved battery performance, wherein the internal resistance caused by contacting with the positive electrode mix is remarkably reduced and the corrosion resistance is excellent. It also aims to produce the material, wherein powdering is reduced at the inner surface of the battery container during forming. Furthermore, it aims to produce a battery container manufactured using the material and a battery manufactured using the battery container. The surface treated steel sheet of the present invention for a battery container is comprising a steel substrate on which one side to be the inner surface of the battery container nickel- tin-iron diffusion layer is formed on the uppermost surface. On the side to be the outer surface of the battery container nickel-cobalt-iron diffusion layer is formed on the uppermost surface.

Abstract: A method for treating metal workpieces, including non-ferrous metal workpieces such as Titanium. The metal workpieces are heat soaked for a predetermined amount of time in a furnace at a predetermined temperature. An interstitial element is introduced into the area adjacent to the surface of the metal workpieces until a predetermined concentration of the interstitial element exists in the area adjacent to the metal workpieces. The treated metal workpieces are then cooled, resulting in the metal workpieces having a diffusion region formed which extends into the body of the metal workpieces. The region has a gradient of the interstitial element formed therein.

Abstract: There is provided a surface alloyed component which comprises a base alloy with a diffusion barrier layer enriched in silicon and chromium being provided adjacent thereto. An enrichment pool layer is created adjacent said diffusion barrier and contains silicon and chromium and optionally titanium or aluminum. A reactive gas treatment may be used to generate a replenishable protective scale on the outermost surface of said component.

Abstract: A coating composition and process have been developed to provide an activated coating on nickel screen for use as cathodes in electrolytic cells for the generation of hydrogen and oxygen. Compared to the earlier Classical Pack Cementation process, the disclosed process is less expensive, reduces processing time from 20 hours to a few minutes, eliminates dusts and toxic gases, and provides improved performance in cells for hydrogen and oxygen generation. The coating is characterized by the presence of two activated layers with a high surface area, a multitude of fissures and a nickel to aluminum weight ratio greater than 20/1 in the top layer and greater than 4/1 in the bottom layer adjacent to the nickel substrate.

Abstract: A thermal barrier coating system and a method for forming the coating system on an article. The coating system employs a bond coat of a nickel aluminide alloy over which a thermal-insulating ceramic layer is deposited. The nickel aluminide bond coat contains zirconium, but is otherwise predominantly of the beta (&bgr;) NiAl phase. The bond coat is preferably deposited by a physical vapor deposition process to have a fine-grain microstructure and a limited diffusion zone in the article surface.

Abstract: A part or jig of a metal for a gas carburizing furnace has an Al diffusion layer which has an Al content of 10 to 50 wt % in the surface portion of the part or jig, the Al diffusion layer being formed by carrying out the calorizing treatment.

Abstract: The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants which may enter the composite body. The getterer materials may be placed into at least a portion of the composite body such that any undesirable oxidant approaching, for example, a fiber reinforcement, would be scavenged by (e.g., reacted with) the getterer. The getterer materials) may form at least one compound which acts as a passivation layer, and/or is able to move by bulk transport (e.g., by viscous flow as a glassy material) to a crack, and sealing the crack, thereby further enhancing the oxidation protection of the composite body.

Abstract: A cutting insert which comprises a rake face and a flank face wherein there is a cutting edge at the juncture of the rake face and the flank face. The cutting insert has a coating and a substrate wherein the coating is adherently bonded to the substrate. The substrate is a tungsten carbide-based cemented carbide wherein there is a zone of non-stratified cobalt enrichment beginning near and extending inwardly from a peripheral surface of the substrate. The bulk substrate has a porosity of greater than C00 and less than or equal to C04.

Abstract: A family of aluminoborate glasses that are compatible with aluminum at elevated temperatures, and an article comprising such a glass with either an aluminum coating, or with aluminum particles dispersed within the glass, whereby the glass may be rendered polarizing. The base glass consists essentially of, 15-85% B2O3, 5-45% Al2O3 and 10-75% Li2O+RO, where RO represents the alkaline earth metal oxides MgO, CaO, SrO and BaO, and is free of oxides reacting with aluminum at elevated temperatures.

Abstract: The contact material of the present invention comprises: an anti-arcing constituent consisting of at least one TiC, V and VC of which the content is 30˜70 volume % and whose mean particle (grain) size is 0.1˜9 &mgr;m; C whose content is 0.005˜0.5 weight % with respect to the anti-arcing constituent, whose diameter is 0.01˜5 &mgr;m when its shape is calculated as spherical, and which is in non-solid solution condition or condition in which it does not form a chemical compound; and a conductive constituent consisting of Cu and constituting the balance.

Abstract: The present invention includes a method of repairing an annular metallic article and the repaired article itself which has an axially extending annular support and a projection generally radially extending therefrom. The projection has an associated operating radial height as measured from a radially facing annular first surface of the support and an associated shape. An upper portion of the projection is removed forming a stub extending away from the first surface and having a bonding surface at a stub end spaced apart from the first surface. A metallic material is metallurgically bonded to the bonding surface forming an annular heat affected zone in the stub bounded by the bonding surface. A first portion of the metallic material is removed to restore the projection to the operating height and shape. At least one annular outer surface of the tooth extending over at least a portion of the heat affected zone is laser shock peened, preferably after the first portion of the metallic material is removed.

Abstract: A support for a lithographic printing plate in which uniform pits are efficiently formed by electrochemically graining treatment, always independently of electrolytic conditions to give excellent printing performance, which comprises an aluminum alloy plate containing 0.05% to 0.5% by weight of Fe, 0.03% to 0.15% of Si, 0.006% to 0.03% by weight of Cu and 0.010% to 0.040% by weight of Ti, wherein the Cu concentration of a surface layer portion of from a surface to a depth of 2 &mgr;m of the aluminum alloy plate is at least 20 ppm higher than that of a region deeper than the surface layer portion.

Abstract: There is provided a method of fabricating a ferromagnetic tunnel junction device, including the steps of (a) forming a first ferromagnetic layer on a substrate, (b) forming a tunnel barrier layer on the first ferromagnetic layer, (c) forming a second ferromagnetic layer on the tunnel barrier layer, (d) mechanically polishing end surfaces of the first ferromagnetic layer, the tunnel barrier layer, and the second ferromagnetic layer, and (e) etching the surfaces of the first ferromagnetic layer, the tunnel barrier layer, and the second ferromagnetic layer. The method provides a ferromagnetic tunnel junction device having a height defined with high accuracy, and including a tunnel barrier layer keeping first and second ferromagnetic layers in electrical isolation with each other.

Abstract: An article is described, which includes a metal-based substrate, such as a superalloy; a dense, primary bond layer; and a spongy secondary bond layer. A thermal barrier coating is applied over the secondary bond layer. The spongy layer has a microstructure which includes an open network of interconnected pores. A process is also described. It includes the step of applying a spongy, metallic bond layer over the substrate, followed by the application of a thermal barrier coating. A dense, primary bond layer may optionally be applied before the application of the spongy layer.