1、Designation: C1835 16Standard Classification forFiber Reinforced Silicon Carbide-Silicon Carbide (SiC-SiC)Composite Structures1This standard is issued under the fixed designation C1835; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This classification covers silicon carbide-silicon carbide(SiC-SiC) composite structures (flat plates,
3、rectangular bars,round rods, and tubes) manufactured for structural compo-nents. The SiC-SiC composites consist of continuous siliconcarbide fibers in a silicon carbide matrix produced by fourdifferent matrix densification methods.1.2 The classification system provides a means of identify-ing and or
4、ganizing different SiC-SiC composites, based on thefiber type, architecture class, matrix densification, physicalproperties, and mechanical properties. The system provides atop-level identification system for grouping different types ofSiC-SiC composites into different classes and provides a meansof
5、 identifying the general structure and properties of a givenSiC-SiC composite. It is meant to assist the ceramics commu-nity in developing, selecting, and using SiC-SiC compositeswith the appropriate composition, construction, and propertiesfor a specific application.1.3 The classification system pr
6、oduces a classification codefor a given SiC-SiC composite, which shows the type of fiber,reinforcement architecture, matrix type, fiber volume fraction,density, porosity, and tensile strength and modulus (roomtemperature).1.3.1 For example, Composites Classification Code, SC2-A2C-4D10-33a SiC-SiC co
7、mposite material/component(SC2) with a 95 %+ polymer precursor (A) based siliconcarbide fiber in a 2D (2) fiber architecture with a CVI matrix(C), a fiber volume fraction of 45 % (4 = 40 to 45 %), a bulkdensity of 2.3 g/cc (D = 2.0 to 2.5 g/cc), an apparent porosityof 12 % (10 = 10 to 15 %), an aver
8、age ultimate tensile strengthof 350 MPa (3 = 300 to 399 MPa), and an average tensilemodulus of 380 GPa (3 = 300 to 399 GPa).1.4 This classification system is a top level identificationtool which uses a limited number of composite properties forhigh level classification. It is not meant to be a compl
9、ete,detailed material specification, because it does not cover thefull range of composition, architecture, physical, mechanical,fabrication, and durability requirements commonly defined in afull design specification. Guide C1793 provides extensive anddetailed direction and guidance in preparing a co
10、mplete mate-rial specification for a given SiC-SiC composite component.1.5 UnitsThe values stated in SI units are to be regardedas standard. No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its
11、 use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C242 Terminology of Ceramic Whitewares and RelatedProductsC559 Test Meth
12、od for Bulk Density by Physical Measure-ments of Manufactured Carbon and Graphite ArticlesC1039 Test Methods for Apparent Porosity, Apparent Spe-cific Gravity, and Bulk Density of Graphite ElectrodesC1145 Terminology of Advanced CeramicsC1198 Test Method for Dynamic Youngs Modulus, ShearModulus, and
13、 Poissons Ratio for Advanced Ceramics bySonic ResonanceC1259 Test Method for Dynamic Youngs Modulus, ShearModulus, and Poissons Ratio for Advanced Ceramics byImpulse Excitation of VibrationC1275 Test Method for Monotonic Tensile Behavior ofContinuous Fiber-Reinforced Advanced Ceramics withSolid Rect
14、angular Cross-Section Test Specimens at Am-bient TemperatureC1773 Test Method for Monotonic Axial Tensile Behaviorof Continuous Fiber-ReinforcedAdvanced Ceramic Tubu-lar Test Specimens at Ambient TemperatureC1793 Guide for Development of Specifications for Fiber1This classification is under the juri
15、sdiction of ASTM Committee C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.07 onCeramic Matrix Composites.Current edition approved Feb. 1, 2016. Published March 2016. DOI: 10.1520/C1835-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS
16、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1Reinforced Silicon Carbide-Si
17、licon Carbide CompositeStructures for Nuclear ApplicationsD3878 Terminology for Composite MaterialsD4850 Terminology Relating to Fabrics and Fabric TestMethodsD6507 Practice for Fiber Reinforcement Orientation Codesfor Composite MaterialsE6 Terminology Relating to Methods of Mechanical TestingE111 T
18、est Method for Youngs Modulus, Tangent Modulus,and Chord ModulusE1309 Guide for Identification of Fiber-ReinforcedPolymer-Matrix Composite Materials in Databases (With-drawn 2015)33. Terminology3.1 General DefinitionsMany of the terms in this classi-fication are defined in the terminology standards
19、for ceramicwhitewares (C242), advanced ceramics (C1145), compositematerials (D3878), fabrics and fabric test methods (D4850),and mechanical testing (E6).3.1.1 apparent porosity, nthe volume fraction of all pores,voids, and channels within a solid mass that are interconnectedwith each other and commu
20、nicate with the external surface,and thus are measurable by gas or liquid penetration. (Syn-onym open porosity) C2423.1.2 braided fabric, na woven structure produced byinterlacing three or more ends of yarns in a manner such thatthe paths of the yarns are diagonal to the vertical axis of thefabric.3
21、.1.2.1 DiscussionBraided structures can have 2D or 3Darchitectures. D48503.1.3 bulk density, nthe mass of a unit volume of materialincluding both permeable and impermeable voids. C5593.1.4 ceramic matrix composite, na material consisting oftwo or more materials (insoluble in one another), in which t
22、hemajor, continuous component (matrix component) is a ceramic,while the secondary component(s) (reinforcing component)may be ceramic, glass-ceramic, glass, metal, or organic innature. These components are combined on a macroscale toform a useful engineering material possessing certain proper-ties or
23、 behavior not possessed by the individual constituents.C11453.1.5 fabric, nin textiles, a planar structure consisting ofyarns or fibers. D48503.1.6 fiber, na fibrous form of matter with an aspect ratio10 and an effective diameter 90% density to produce a finalstructure with orthotropic or quasi-isot
24、ropic mechanical and thermalproperties.5.5 The silicon carbide matrix in SiC-SiC composites iscommonly produced by one of four methods (12): (1) achemical vapor infiltration process, (2) an iterative precursorliquid infiltration/pyrolysis process, (3) a silicon melt infiltra-tion process, or (4) hot
25、 pressing and sintering of SiC powders.The four matrix formation processes use different precursorsand different processing conditions, which produce differencesin the chemistry, phase composition and fractions, crystallinity,morphology, and microstructure (density, pores, and cracks) inthe silicon
26、carbide matrix. Two or more of these matrixdensification processes may be combined for a hybrid siliconcarbide matrix.5.6 In some SiC-SiC composite applications an inorganicsurface seal coating is applied to the outer surface of thecomposite to protect against high temperature oxidation andcorrosion
27、 attack or to improve wear and abrasion resistance.Such coatings are commonly hard, impermeable ceramiccoatings.5.7 The interaction of these four variable factor sets (1)silicon carbide fiber type and properties; (2) fiber interfacecoating; (3) fiber content, tow structure, and architecture; (4)matr
28、ix composition and properties, phase content, crystallinity,density, morphology, and porosity can produce SiC-SiC com-posites with a wide range of mechanical and physicalproperties, along with tailored anisotropic properties in themajor directions.6. Classification of Silicon Carbide-Silicon Carbide
29、Composites6.1 GeneralSiC-SiC composites for structural applica-tions can be classified by fiber type, architecture class, matrixgrade, physical properties, and mechanical properties.6.2 Fiber TypesThe SiC-SiC composites are type classi-fied based on the stoichiometry and the fabrication method ofthe
30、 silicon carbide fiber.6.2.1 Type A95 atomic % stoichiometric crystalline SiCby polymer precursor;6.2.2 Type B80-95 atomic % stoichiometric crystallineSiC by polymer precursor;6.2.3 Type C45 %), a bulk density of 3.1 g/cc (A = 3.0 g/cc), an apparentporosity of 400 MPa), and an average tensilemodulus
31、 of 360 GPa (3 = 300-399 GPa).7. Keywords7.1 classification; mechanical properties; physical proper-ties; silicon carbide composites; silicon carbide fiberTABLE 1 Classification Codes for SiC-SiC Composites for Structural ApplicationsOrder Property Classification Codes1 Fiber Type A 95%Stoichiometri
32、c SiCFibers by PPB 80-95%Stoichiometric SiCFibers by PPC 45% 40-45% 30-39% 20-29% 3.0 2.8-2.99 2.5-2.79 2.0-2.49 15%TABLE 3 Mechanical Property Classification Level Codes for SiC-SiC CompositesNOTE 1Four-point flexure strength and modulus properties are not an acceptable alternative to tensile prope
33、rties for the classification process, becauseof the variability produced by different flexure specimen geometries and test configurations.Mechanical Property Geometry Direction Level Codes43211*Average Ultimate Tensile or Hoop StrengthA(MPa) by Test Methods C1275 and C1773Plate / Bar Primary Axis 0R
34、od / Tube Axial or HoopA400 MPa 300-399 MPa 200-299 MPa 100-199 MPa 400 GPa 300-399 GPa 200-299 GPa 100-199 GPa 100 GPaAFor composite tubes where hoop strength may be the primary strength requirement, the classification system may reference the hoop strength and hoop modulus, ratherthan the axial tensile strength and modulus. This will be marked by an “H” subscript on the Level Code: 5H,3H, etc.C1835 166
