Abstract: A superalloy target wherein the superalloy target has a polycrystalline structure of random grain orientation, the average grain size in the structure is smaller than 20 ?m, and the porosity in the structure is smaller than 10%. Furthermore, the invention includes a method of producing a superalloy target by powder metallurgical production, wherein the powder-metallurgical production starts from alloyed powder(s) of a superalloy and includes the step of spark plasma sintering (SPS) of the alloyed powder(s).

Abstract: A composite material having an alloy matrix including titanium, aluminum, niobium, manganese, boron, and carbon is disclosed. The composite material includes, by atomic percentage, 40.0% to 50.0% Al, 1.0% to 8.0% Nb, 0.5% to 2.0% Mn, 0.1% to 2.0% B, and 0.01% to 0.2% C. The composite material is doped with a solid lubricant such as MoS2, ZnO, CuO, hexagonal boron nitride (hBN), WS2, AgTaO3, CuTaO3, CuTa2O6, or combinations thereof. Components composed of the composite material exhibit increased ductility at room temperature and reduced fracture tendency, resulting in improved durability.

Abstract: The present invention relates to an amorphous alloy having low frictional resistance and capable of improving abrasion resistance, a target made of the amorphous alloy, and a compressor comprising a layer of the amorphous alloy as a coating layer. According to the present invention, it is possible to secure high hardness and a low elastic modulus of the coating layer by controlling a microstructure having an amorphous phase as a primary phase by using Ti-based three-component to five-component amorphous alloys. As a result, it is possible to prevent the coating layer from being peeled off from a matrix or destroyed, and thus it is possible to achieve the effect of improving reliability or durability of a mechanical apparatus such as a compressor.

Abstract: A composition and medical implant made therefrom, the composition including a thick diffusion hardened zone, and preferably further including a ceramic layer. Also provided are orthopedic implants made from the composition, methods of making the composition, and methods of making orthopedic implants from the composition.

Abstract: A titanium-based alloy includes 0.001-1.0 wt. % in total of at least one lanthanide series element, remainder of titanium and impurities.

Abstract: A Ti-6A1-4V titanium powder alloy composition having enhanced strength resulting from the addition of one or more of the following elements without requiring an increase in oxygen content: Aluminum Iron Nitrogen Carbon The composition may also be used for Ti-6A1-4V titanium alloy starting bar stock.

Abstract: The disclosure relates to a titanium alloy, in particular to be used for biocompatible implants, which contains no aluminum (Al), vanadium (V), cobalt (Co), chromium (Cr), nickel (Ni) and tin (Sn) and contains at least the following alloy components in wt % in addition to inevitable trace amounts of impurities contained in the alloy components or absorbed during the production: a) 0.2 to 1.5% oxygen (O), b) 0.1 to 1.5% iron (Fe), c) 0.01 to 2% carbon (C), d) the remainder being titanium (Ti).

Abstract: A titanium plate is provided in which a Vickers hardness Hv0.025 at a load of 0.245 N at a surface is 150 or less, and an average length of the profile elements RSm is 80 ?m or less and a maximum height Rz is less than 1.5 ?m, RSm and Rz being as defined in JIS B 0601: 2013. The titanium plate has good surface deformability.

Abstract: Methods and apparatus for reducing defects in a workpiece are provided herein. In some embodiments, a sputter deposition target is provided for reducing defects in a workpiece, the target comprising a dielectric compound having a predefined average grain size ranging from approximately 20 ?m to 200 ?m. In other embodiments, a process chamber is provided, the process chamber comprising a chamber body defining an interior volume, a substrate support to support a substrate within the interior volume, a plurality of targets to be sputtered onto the substrate including at least one dielectric target, wherein the dielectric target comprises a dielectric compound having a predefined average grain size ranging from approximately 20 ?m to 200 ?m and a shield rotatably coupled to an upper portion of the chamber body and having at least one hole to expose at least one of the plurality of targets to be sputtered.

Abstract: Titanium alloys formed into a part or component used in applications where a key design criterion is the energy absorbed during deformation of the part when exposed to impact, explosive blast, and/or other forms of shock loading is described. The titanium alloys generally comprise a titanium base with added amounts of aluminum, an isomorphous beta stabilizing element such as vanadium, a eutectoid beta stabilizing element such as silicon and iron, and incidental impurities. The titanium alloys exhibit up to 70% or more improvement in ductility and up to a 16% improvement in ballistic impact resistance over a Ti-6Al-4V alloy, as well as absorbing up to 50% more energy than the Ti-6Al-4V alloy in Charpy impact tests. A method of forming a part that incorporates the titanium alloys and uses a combination of recycled materials and new materials is also described.

Abstract: A vanadium alloy essentially consisting of: vanadium; and aluminium having a content of greater than 0 to 10 at %, and a process of producing thereof.

Abstract: A Ti-6A1-4V titanium powder alloy composition having enhanced strength resulting from the addition of one or more of the following elements without requiring an increase in oxygen content: Aluminum Iron Nitrogen Carbon The composition may also be used for Ti-6A1-4V titanium alloy starting bar stock.

Abstract: Disclosed herein are embodiments of hardfacing alloys which can be resistant to hot tearing and cracking. In doing so, the hardfacing alloys can meet certain thermodynamic, microstructural, and performance criteria. For example, embodiments of the alloy have a martensitic matrix embedded with isolated carbides and/or borides. Further, in some embodiments the hardfacing alloys can also have high levels of macro-hardness.

Abstract: The present invention relates to a TiAl alloy for use at high temperatures which has aluminum and titanium as main constituents. The TiAl alloy has an aluminum content of greater than or equal to 50 at. % and a matrix of ?-TiAl and at least one phase of Al and Ti incorporated in the ?-TiAl matrix which is different from ?-TiAl, as well as depositions of oxides and/or carbides and/or silicides. In addition, the invention relates to a method for producing the alloy and to the use of the alloy for components of turbo-machines, in particular aircraft engines.

Abstract: A method (101) is provided for making a scandium-containing alloy. The method includes providing a molten metal (103), and mixing the molten metal with a scandium-containing precursor (113) which undergoes thermal decomposition at the temperature of the molten metal to produce scandium oxide, thereby producing a scandium-containing alloy.

Abstract: An alloy composition that includes about 1 to about 9 atomic percent aluminum (Al), about 25 to about 33 atomic percent titanium (Ti), about 10 to about 33 atomic percent vanadium (V), about 5 to about 10 atomic percent zirconium (Zr) and about 25 to about 33 atomic percent niobium (Nb).

Abstract: A method of producing a nano twinned commercially pure titanium material includes the step of casting a commercially pure titanium material, that apart from titanium, contains not more than 0.05 wt % N; not more than 0.08 wt % C; not more than 0.015 wt % H; not more than 0.50 wt % Fe; not more than 0.40 wt % O; and not more than 0.40 wt % residuals. The material is brought to a temperature at or below 0° C. and plastic deformation is imparted to the material at that temperature to such a degree that nano twins are formed in the material.

Abstract: It is an objective of the invention to provide a steam turbine rotor of which a rotor shaft is made of a low-cost heat resistant ferritic steel and that can withstand high main steam temperatures of about 650° C. There is provided a steam turbine rotor comprising: a rotor shaft made of a heat resistant ferritic steel such as a 12-Cr steel; and a rotor blade made of a Ti—Al alloy, wherein the Ti—Al alloy includes: from 38 to 45 atomic % of Al; from 0.5 to 2 atomic % of V; from 2 to 6 atomic % of Cr and/or Mo; and the balance being Ti and incidental impurities.

Abstract: A vaso-occlusive device is constructed out of dissimilar metallic materials that are in contact or otherwise in close proximity with one another, thereby causing the device to undergo galvanic corrosion when exposed to an electrolytic medium, such as blood or other body fluid, wherein one of the dissimilar metallic materials is zirconium or zirconium alloy to create a corrosive product including zirconia having a relatively high hardness, a relatively high fracture toughness, and a relatively high stability when the device is implanted in a vasculature site, such as an aneurysm.

Abstract: A production method for a titanium alloy member includes preparing a titanium alloy material for sintering as a raw material of a sintered body; nitriding the titanium alloy material for sintering, thereby forming a nitrogen compound layer and/or a nitrogen solid solution layer in a surface layer of the titanium alloy material for sintering and yielding a nitrogen-containing titanium alloy material for sintering; mixing the titanium alloy material for sintering and the nitrogen-containing titanium alloy material for sintering, thereby yielding a titanium alloy material for sintering mixed with nitrogen-containing titanium alloy material; sintering the titanium alloy material for sintering mixed with nitrogen-containing titanium alloy material, thereby bonding the material each other and dispersing nitrogen contained in the nitrogen-containing titanium alloy material for sintering in a condition in which nitrogen is uniformly dispersed into an entire inner portion of the sintered body by solid solution.

Abstract: An amorphous and nano nitride composite thin film, a method for forming the same, and an electronic device having the same are provided. The amorphous and nano nitride composite thin film has a composite structure in which a nitride phase that includes Zr and Al as nitride constituent elements and at least one metal phase are mixed, wherein the metal phase includes at least one element selected from the group including Cu and Ni, the nitride phase includes a ZrN crystalline phase in which a size of a grain is in the range of 10 nm to 500 nm, and a volume fraction of the ZrN crystalline phase is 10% or more.

Abstract: A cold rollable beta titanium alloy is provided by the present disclosure that exhibits excellent tensile strength, and creep and oxidation resistance at elevated temperatures. In one form, the beta titanium alloy includes molybdenum in an amount ranging between 13.0 wt. % to 20.0 wt. %, niobium between 2.0 wt. % to 4.0 wt. %, silicon between 0.1 wt. % to 0.4 wt. %, aluminum between 3.0 wt. % to 5.0 wt. %, at least one of: zirconium up to 3.0 wt. % and tin up to 5.0 wt. %, oxygen up to 0.25 wt. %, and a balance of titanium and incidental impurities. Additionally, the ranges for each element satisfies the conditions of: 6.0 wt. %?X wt. %?7.5 wt. %; and??(i) 3.5 wt. %?Y wt. %?5.15 wt. %, where??(ii) X wt. %=aluminum+tin/3+zirconium/6+10*(oxygen+nitrogen+carbon), and Y wt. %=aluminum+silicon*(zirconium+tin).

Abstract: Disclosed is a TiAl alloy for high-temperature applications which comprises not more than 43 at. % of Al, from 3 at. % to 8 at. % of Nb, from 0.2 at. % to 3 at. % of Mo and/or Mn, from 0.05 at. % to 0.5 at. % of B, from 0.1 at. % to 0.5 at. % of C, from 0.1 at. % to 0.5 at. % of Si and Ti as balance. Also disclosed is a process for producing a component made of this TiAl alloy and the use of corresponding TiAl alloys in components of flow machines at operating temperatures up to 850° C.

Abstract: A method for producing a Ti-6Al-4V article, includes providing a work piece of a Ti-6Al-4V alloy having a beta-transus temperature; subjecting the work piece to a beta solution heat treatment process in a furnace with a vacuum at a temperature above the beta transus; quenching the work piece in the furnace using high pressure inert gas following the subjecting of the work piece in the beta solution heat treatment process; and subjecting the work piece to an overage heat treatment process in the furnace with a vacuum to overage the work piece following the quenching of the work piece. The work piece can be a bolt blank that is further manufactured into a titanium bolt with pre-machined wave form threads and wave form rolling process utilized to manufacture threads into the bolt blank.

Abstract: A welding wire formed of a trace boron titanium base alloy is provided, along with welds formed from the wire and articles comprising one or more of such welds. A method may include forming such a weld or welds from such a welding wire, and may also include non-destructively inspecting titanium alloy articles comprising one or more of such welds using ultrasonic waves to detect internal flaws.

Abstract: A copper alloy sputtering target most suitable for formation of an interconnection material of a semiconductor device, particularly for formation of a seed layer, characterized in that the target contains 0.4 to 5 wt % of Sn, and the structure of the target does not substantially contain any precipitates, and the resistivity of the target material is 2.2 ??cm or more. This target enables formation of an interconnection material of a semiconductor device, particularly a uniform seed layer stable during copper electroplating and is excellent in sputtering deposition characteristics. A method for manufacturing such a target is also disclosed.

Abstract: A process includes sintering hydrogenated titanium or titanium hydride (TiH2) and/or Ti metal in a dynamically controlled hydrogen atmosphere with hydrogen partial pressure greater than 0.

Abstract: Laves phase-related BCC metal hydride alloys historically have limited electrochemical capabilities. Provided are processes of activating these alloys to produce hydrogen storage materials with greater than 200 mAh/g capacities and commonly much greater than 300 mAh/g capacities. The processes include cooling the alloy during hydrogenation to reduced temperatures or by subjecting the materials to significantly increased hydrogen pressures. Temperatures in many embodiments do not exceed 300° C. By decreasing the temperature or increasing the hydrogen pressure the phase structure of the material is optimized to increase a synergistic effect between multiple phases in the resulting alloy thereby greatly improving the electrochemical capacities.

Abstract: Provided is a super elastic alloy for biological use having a high biocompatibility, good processability and super elasticity, said super elastic alloy being a super elastic zirconium alloy for biological use comprising 27-54 mol % inclusive of titanium, 5-9 mol % inclusive of niobium which is a ? phase-stabilizing element capable of stabilizing the ? phase of zirconium, and 1-4 mol % inclusive in total of tin and/or aluminum which are ? phase-suppressing elements capable of suppressing the ? phase of zirconium, with the balance consisting of zirconium and inevitable impurities.

Abstract: A titanium alloy includes 15 to 27 atomic % (at %) of tantalum (Ta) and 0 to 8 at % of tin (Sn), the balance being titanium (Ti) and unavoidable impurities, when the entire amount of the titanium alloy is taken as 100 at %. Therefore, the titanium alloy provided has characteristics suitable for medical device materials, biocompatible materials, etc.

Abstract: “To provide, at low cost, a resource saving-type titanium alloy that uses alloy elements more abundant in resources and more inexpensively available compared to conventional titanium alloys, and, when added even in a smaller amount than the conventional alloys, can simultaneously realize both high strength and high toughness. Provided is a titanium alloy member having excellent strength and toughness, consisting of, in mass %, Al: more than or equal to 4.5% and less than 5.5%, Fe: more than or equal to 1.3% and less than 2.3%, Si: more than or equal to 0.25% and less than 0.50%, O: more than or equal to 0.05% and less than 0.25%, and the balance: titanium and unavoidable impurities. The titanium alloy member has a microscopic structure that is an acicular structure having an acicular ? phase with a mean width of less than 5 pm.

Abstract: Approaches for providing a liner at a via-to-wire interface are provided. A method includes: forming a via opening that exposes an upper surface of a copper wire; forming a titanium liner on the upper surface of the wire; forming a tungsten liner on the titanium liner; and forming a via on the second liner in the via opening.

Abstract: The present invention relates to a Ti—Al-based heat-resistant member including a Ti—Al-based alloy which includes: 28.0 mass % to 35.0 mass % of Al; 1.0 mass % to 15.0 mass % of at least one selected from the group consisting of Nb, Mo, W and Ta; 0.1 mass % to 5.0 mass % of at least one selected from the group consisting of Cr, Mn and V; and 0.1 mass % to 1.0 mass % of Si, with the balance being Ti and unavoidable impurities, in which a whole or a part of a surface of the Ti—Al-based heat-resistant member includes a hardened layer as a surface layer, the hardened layer having a higher hardness than an inside of the Ti—Al-based heat-resistant member, and the Ti—Al-based heat-resistant member has a hardness ratio (a hardness of the surface layer/a hardness of the inside) of 1.4 to 2.5.

Abstract: An ?+? type hot-rolled titanium alloy sheet, wherein: (a) ND represents the normal direction of a hot-rolled sheet; RD represents the hot rolling direction; TD represents the hot rolling width direction; ? represents the angle formed between the orientation of c axis and the ND; ? represents the angle formed between a plane including the orientation of the c axis and the ND, and a plane including the ND and the TD; (b1) XND represents the highest (0002) relative intensity of the X-ray reflection caused by crystal grains when ? is from 0° to 30° and ? is within the entire circumference; (b2) XTD represents the highest (0002) relative intensity of the X-ray reflection caused by crystal grains when ? is from 80° to 100° and ? is ±10°. (c) The ?+? type titanium alloy sheet has a value for XTD/XND of at least 5.0.

Abstract: One aspect of the present disclosure is directed to a metastable ? titanium alloy comprising, in weight percentages: up to 0.05 nitrogen; up to 0.10 carbon; up to 0.015 hydrogen; up to 0.10 iron; greater than 0.20 oxygen; 14.00 to 16.00 molybdenum; titanium; and incidental impurities. Articles of manufacture including the alloy also are disclosed.

Abstract: Disclosed are a composite transparent electrode, a production method thereof, and an electronic device including the same, wherein the composite transparent electrode includes a metal nitride thin film including at least one of indium (In), titanium (Ti), zinc (Zn), zirconium (Zr), and gallium (Ga), and a metal oxide thin film including at least one of indium (In), zinc (Zn), tin (Sn), and titanium (Ti), the metal oxide thin film being formed on one surface or opposite surfaces of the metal nitride thin film.

Abstract: According to a thermomechanical treatment process for a titanium alloy including between 23 and 27% niobium in atomic proportion, between 0 and 10% zirconium, and between 0 and 1% oxygen, nitrogen and/or silicon, the following steps are performed: a) an increase of a sample of the alloy to a temperature higher than 900° C., b) a fast quench, c) a severe cold strain, d) an ageing treatment at a temperature included between 200 and 600° C., the time of the ageing treatment being included between 10 seconds and 10 minutes. Alloy obtained by this process and prostheses made from such an alloy.

Abstract: A method of coating a stent is provided that minimizes damage to the coating. The stent is self-expanding and made of a superelastic material. The stent is initially cooled so that at least part of the structure of the stent transforms to a martensitic phase. The stent is then compressed, coated and loaded while the structure of the stent remains at least partially martensitic. After the stent is loaded into a tubular restraint, the loaded stent is allowed to warm to room temperature.

Abstract: A medical device includes an alloy having a microstructure that provides desirable properties. The alloy can be a eutectoid composition of e.g. titanium as a major constituent and any combination of iridium, platinum, chromium, gold, silver, bismuth, manganese, palladium, cobalt, copper, iron, and/or nickel as a minor constituent, wherein the alloy forms at least a portion of the medical device.

Abstract: In accordance with an exemplary embodiment, a method of forming a ceramic reinforced titanium alloy includes the steps of providing, in a pre-alloy powdered form, a ceramic reinforced titanium alloy composition that is capable of achieving a dispersion-strengthened microstructure, directing a low energy density energy beam at a portion of the alloy composition, and forming a ceramic reinforced titanium alloy metal having ceramic particulates of less than 10 ?m on a weight-average basis. The step of forming includes the sub-steps of withdrawing the energy beam from the portion of the powdered alloy composition and cooling the portion of the powdered alloy composition at a rate greater than or equal to about 106° F. per second, thereby forming the ceramic reinforced titanium alloy metal.

Abstract: A dental prosthesis component which is a member for configuring a dental prosthesis provided with an artificial tooth root, which has a high strength and a good esthetic property. The dental prosthesis component which is a member for configuring a dental prosthesis provided with an artificial tooth root wherein the dental component is made of Zr-14Nb alloy, a surface layer containing ZrO2 as a main constituent and having a thickness of 20 ?m or more and less than 80 ?m is formed on the dental prosthesis component, and the surface has a brightness of Gy 8.0 or more of the color sheets according to Practical Color Co-ordinate System 201.

Abstract: A titanium alloy product according to the present invention: has a strength level higher than that of an existing titanium alloy product; can be successfully cold rolled (coil rolled); and is also provided with workability. In the titanium alloy product according to the invention, expensive alloy elements are not essentially required, and hence cost can be suppressed. The titanium alloy product according to the invention includes Al equivalent represented by (Al+10O (oxygen)): 3.5 to 7.2% (% by mass, the same hereinafter), Al: more than 1.0% and 4.5% or less, O: 0.60% or less, Fe equivalent represented by (Fe+0.5Cr+0.5Ni+0.67Co+0.67Mn): 0.8% or more and less than 2.0%, and one or more elements selected from the group consisting of Cu: 0.4 to 3.0% and Sn: 0.4 to 10%, in which the balance is Ti and unavoidable impurities.

Abstract: Disclosed herein are zirconium-based alloys and methods of fabricating nuclear reactor components, particularly fuel cladding tubes, from such alloys that exhibit improved corrosion resistance in aggressive coolant compositions. The fabrication steps include a late-stage ?-treatment on the outer region of the tubes. The zirconium-based alloys will include between about 1.30 and 1.60 wt % tin; between about 0.06 and 0.15 wt % chromium; between about 0.16 and 0.24 wt % iron, and between 0.05 and 0.08 wt % nickel, with the total content of the iron, chromium and nickel comprising above about 0.31 wt % of the alloy and will be characterized by second phase precipitates having an average size typically less than about 40 nm. The final finished cladding will have a surface roughness of less than about 0.50 ?m Ra and preferably less then about 0.10 ?m Ra.

Abstract: Articles that are cast from a particular titanium alloy can achieve a relatively high fatigue strength. The titanium alloy is an (?+?) titanium alloy that has a nominal composition of about 5.5 to about 6.63 mass percent aluminum, about 3.5 to about 4.5 mass percent vanadium, about 1.0 to about 2.5 mass percent chromium, maximum of 0.50 mass percent iron, about 0.15 to about 0.25 mass percent oxygen, about 0.06 to about 0.12 mass percent silicon, and at least 80 mass percent titanium or the balance titanium (Ti) with the exception of some allowable impurities. In one exemplary application, this titanium alloy may be used to cast a turbocharger compressor wheel.

Abstract: The invention relates to a method for producing a component from a TiAl alloy, wherein the component is shaped by forging, in particular isothermal forging, and is subsequently subjected to at least one heat treatment, wherein in the first heat treatment the temperature is between 1100 and 1200° C. and is maintained for 6 to 10 hours and then the component is cooled.

Abstract: A high strength near-beta titanium alloy including, in weight %, 5.3 to 5.7% aluminum, 4.8 to 5.2% vanadium, 0.7 to 0.9% iron, 4.6 to 5.3% molybdenum, 2.0 to 2.5% chromium, and 0.12 to 0.16% oxygen with balance titanium and incidental impurities is provided. An aviation system component comprising the high strength near-beta titanium alloy, and a method for the manufacture of a titanium alloy for use in high strength, deep hardenability, and excellent ductility applications are also provided.

Abstract: Titanium alloy that is formed by subjecting titanium alloy to a treatment containing a hydrogen storing step for making the titanium alloy store hydrogen therein, a solution-treatment step for heating the titanium alloy having the hydrogen stored therein in the hydrogen storage step to apply a solution treatment to the hydrogen-stored titanium alloy, a cooling step for cooling the heated hydrogen-stored titanium alloy to develop martensitic transformation in the hydrogen-stored titanium alloy, a hot rolling step for heating the martensitic-transformed titanium alloy to a temperature which is not more than a predetermined transformation point and hot-rolling the martensitic-transformed titanium, and a dehydrogenation step for dehydrogenating the hot-rolled titanium alloy, thereby bringing the titanium alloy with the superplastic property.

Abstract: A process for manufacturing a turbine engine component comprises the steps of: casting ingots made of a gamma TiAl material using a double vacuum arc remelting casting technique; subjecting the cast ingots to a hot isostatic pressing to close porosity; forming at least one pancake of the gamma TiAl material by isothermally forging the hot isostatic pressed ingots; sectioning each pancake into a plurality of blanks; heat treating the blanks to produce a desired microstructure and mechanical properties; and machining the blanks into finished turbine engine components. A system for performing the process is also disclosed.

Abstract: A method for producing a component of a titanium-aluminum base alloy comprising hot isostatically pressing the alloy to form a blank, subjecting the blank to a hot forming by a rapid solid-blank deformation, followed by a cooling of the component to form a deformation microstructure with high recrystallization energy potential, thereafter subjecting the component to a heat treatment in the range of the eutectoid temperature (Teu) of the alloy, followed by cooling in air, to form a homogeneous, fine globular microstructure composed of phases GAMMA, BETA0, ALPHA2 and having an ordered atomic structure at room temperature. This abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: A method of manufacturing a titanium alloy with high strength and high formability includes preparing a material and equipment for manufacturing a titanium alloy, manufacturing a titanium alloy having a lamellar structure (martensite structure) by cooling the prepared material with water after performing heat treatment at the beta transformation temperature or more, and rolling that makes ultrafine grains by finishing forming of the titanium alloy at a plastic instability temperature by gradually decreasing the forming temperature in accordance with an increase of a strain after starting the forming at the plastic instability temperature of more, under a condition of a low strain in which the strain is 2.5 or less, after the manufacturing of a titanium alloy having a lamellar structure.