Download or read book Effects of Interface Coating and Nitride Enhancing Additive on Properites of Hi Nicalon SiC Fiber Reinforced Reaction bonded Silicon Nitride Composites written by Ramakrishna T. Bhatt and published by . This book was released on 2000 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strong and tough Hi-Nicalon SiC fiber reinforced reaction-bonded silicon nitride matirix composites (SiC/RBSN) have been fabricated by the fiber lay-up approach. Commercially available uncoated and PBN, PBN/Si-rich PBN, and BN/SiC coated SiC Hi-Nicalon fiber tows were used as reinforcement. The composites contained ~24 vol % of aligned 14 ♯m diameter SiC fibers in a porous RBSN matrix. Both one- and two-dimensional composites were characterized. The effects of interface coating composition, and the nitridation enhancing additive, NiO, on the room temperature physical, tensile, and interfacial shear strenght properties of SiC/RBSN matrix composites were evaluated. Results indicate that all three coated fibers, the thickness of the coating decreased from the outer periphery to the interior of the tows, and that from 10 to 30 percent of the fibers were not covered with the interface coating.

Download or read book Effects of Interface Coating and Nitride Enhancing Additive on Properties of Hi Nicalon Sic Fiber Reinforced Reaction Bonded Silicon Nitride Composite written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-27 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strong and tough Hi-Nicalon SiC fiber reinforced reaction-bonded silicon nitride matrix composites (SiC/ RBSN) have been fabricated by the fiber lay-up approach. Commercially available uncoated and PBN, PBN/Si-rich PBN, and BN/SiC coated SiC Hi-Nicalon fiber tows were used as reinforcement. The composites contained approximately 24 vol % of aligned 14 micron diameter SiC fibers in a porous RBSN matrix. Both one- and two-dimensional composites were characterized. The effects of interface coating composition, and the nitridation enhancing additive, NiO, on the room temperature physical, tensile, and interfacial shear strength properties of SiC/RBSN matrix composites were evaluated. Results indicate that for all three coated fibers, the thickness of the coatings decreased from the outer periphery to the interior of the tows, and that from 10 to 30 percent of the fibers were not covered with the interface coating. In the uncoated regions, chemical reaction between the NiO additive and the SiC fiber occurs causing degradation of tensile properties of the composites. Among the three interface coating combinations investigated, the BN/SiC coated Hi-Nicalon SiC fiber reinforced RBSN matrix composite showed the least amount of uncoated regions and reasonably uniform interface coating thickness. The matrix cracking stress in SiC/RBSN composites was predicted using a fracture mechanics based crack bridging model. Bhatt, Ramakrishana T. and Hull, David R. and Eldridge, Jeffrey I. and Babuder, Raymond Glenn Research Center NASA/TM-2000-210211, E-12330, NAS 1.15:210211

Download or read book Tensile Properties and Microstructural Characterization of Hi Nicalon SiC RBSN Composites written by and published by . This book was released on 1998 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermal Effects on the Mechanical Properties of SiC Fiber Reinforced Reaction Bonded Silicon Nitride Matrix SiC RBSN Composites written by R. T. Bhatt and published by . This book was released on 1988 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The elevated temperature four-point flexural strength and the room temperature tensile and flexural strength properties after thermal shock were measured for ceramic composites consisting of 30 vol % uniaxially aligned 142 microns diameter SiC fibers in a reaction bonded Si3N4 matrix. The elevated temperature strengths were measured after 15 min of exposure in air at temperatures to 1400 C. The thermal shock treatment was accomplished by heating the composite in air for 15 min at temperatures to 1200 C and then quenching in water at 25 C. The results indicate no significant loss in strength properties either at temperature or after thermal shock when compared with the strength data for composites in the as-fabricated condition. (jes).

Download or read book Oxidation Effects on the Mechanical Properties of SiC Fiber Reinforced Reaction bonded Silicon Nitride Matrix Composites written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-09 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The room temperature mechanical properties of SiC fiber reinforced reaction bonded silicon nitride composites were measured after 100 hrs exposure at temperatures to 1400 C in nitrogen and oxygen environments. The composites consisted of approx. 30 vol percent uniaxially aligned 142 micron diameter SiC fibers in a reaction bonded Si3N4 matrix. The results indicate that composites heat treated in a nitrogen environment at temperatures to 1400 C showed deformation and fracture behavior equivalent to that of the as-fabricated composites. Also, the composites heat treated in an oxidizing environment beyond 400 C yielded significantly lower tensile strength values. Specifically in the temperature range from 600 to 1000 C, composites retained approx. 40 percent of their as-fabricated strength, and those heat treated in the temperatures from 1200 to 1400 C retained 70 percent. Nonetheless, for all oxygen heat treatment conditions, composite specimens displayed strain capability beyond the matrix fracture stress; a typical behavior of a tough composite. Bhatt, Ramakrishna T. Glenn Research Center RTOP 510-01-0A...

Download or read book Effects of Interface Modification on Mechanical Behavior of Hi Nicalon Fiber Reinforced Celsian Matrix Composites written by and published by . This book was released on 1997 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Temperature Tensile Properties of Fiber Reinforced Reaction Bonded Silicon Nitride written by DA. Jablonski and published by . This book was released on 1990 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: A testing technique has been developed for measuring the tensile properties of ceramic matrix composite laminates at temperatures up to 1500°C in air. Using this technique, the tensile properties of unidirectional silicon carbide (SiC) fiber reinforced reaction bonded silicon nitride (SiC/RBSN) composite specimens were measured at 25, 1300, and 1500°C. The composite consists of nearly 30 vol % of aligned 142 μm, chemically vapor deposited SiC fibers (Textron SCS-6). The specimens used were straight section flat specimens with bonded end tabs. A specially designed gripping system was used to minimize bending moment and assured that failure always occurred in the gage section. The specimen extension was measured using a high-temperature capacitive extensometer.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Fiber Matrix Interface and Its Composition on Mechanical Properties of Hi Nicalon Celsian Composites written by Narottam P. Bansal and published by . This book was released on 1999 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ceramic Fibers and Coatings written by Committee on Advanced Fibers for High-Temperature Ceramic Composites and published by National Academies Press. This book was released on 1998-05-05 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-temperature ceramic fibers are the key components of ceramic matrix composites (CMCs). Ceramic fiber properties (strength, temperature and creep resistance, for example)-along with the debonding characteristics of their coatings-determine the properties of CMCs. This report outlines the state of the art in high-temperature ceramic fibers and coatings, assesses fibers and coatings in terms of future needs, and recommends promising avenues of research. CMCs are also discussed in this report to provide a context for discussing high-temperature ceramic fibers and coatings.

Download or read book Influence of Fiber Content on Mechanical Performance of SiC fiber reinforced Reaction bonded Silicon Nitride Composites written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Composite Reinforcements written by Stuart M. Lee and published by John Wiley & Sons. This book was released on 1996-12-17 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive single volume handbook covers every aspect of reinforcement science, from hands-on subjects, such as manual 'lay-up' processing, to theoretical discussions concerning rheology and modeling. Taken from the recently published six volume International Encyclopedia of Composites, this reference volume offers scholarly and practical knowledge of distinguished industry-experts, academics, and government researchers in one accessible and informative handbook. Fibers, processes, and composite reinforcement types, as well as relevant miscellaneous subjects such as property relationships, manufacturing, hybrid reinforcements, and modeling are given detailed treatment. Engineers, materials scientists, and technologists will find the Composite Reinforcement Handbook an invaluable tool.

Download or read book Influence of Interfacial Shear Strength on the Mechanical Properties of SiC Fiber Reinforced Reaction Bonded Silicon Nitride Matrix Composites written by and published by . This book was released on 1990 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of fiber/matrix interface microstructure and interfacial shear strength on the mechanical properties of a fiber-reinforced ceramic composite has been evaluated. The composite consisted of about 30 vol % uniaxially aligned 142 micron diameter SiC fibers (Textron SCS-6) in a reaction- bonded Si3N4 matrix (SiC/RBSN). The interface microstructure was varied by controlling the composite fabrication conditions and by heat treating the composite in an oxidizing environment. Interfacial shear strength was determined by the matrix crack spacing method. The results of microstructural examination indicate that the carbon-rich coating provided with the as-produced SiC fibers was stable in composites fabricated at 1200 C in a nitrogen or in a nitrogen plus 4 percent hydrogen mixture for 40 hr. However this coating degraded in composites fabricated at 1350 C in N2 + 4%H2 for 40 and 72 hr and also in composites heat treated in an oxidizing environment at 600 C for 100 hr after fabrication at 1200 C in a nitrogen. It was determined that degradation occurred by carbon removal which in turn had a strong influence on interfacial shear strength and other mechanical properties. Specifically, as the carbon coating was removed, the composite interfacial shear strength, primary elastic modulus, first matrix cracking stress, and ultimate tensile strength decreased, but the first matrix cracking strain remained nearly the same. Keywords: Ceramic matrix composites; Interfacial shear strength; Mechanical properties.

Download or read book Interfaces in Particle and Fibre Reinforced Composites written by Kheng-Lim Goh and published by Woodhead Publishing. This book was released on 2019-11-27 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interfaces in Particle and Fibre-Reinforced Composites: From Macro- to Nanoscale addresses recent research findings on the particle-matrix interface at different length scales. The book's main focus is on the reinforcement of materials by particles that can result in a composite material of high stiffness and strength, but it also focuses on how the particle interacts with the (matrix) material, which may be a polymer, biological-based material, ceramic or conventional metal. The different types of particle reinforced composites are discussed, as is load transfer at the particle-matrix interface. Readers will learn how to select materials and about particle structure. Significant progress has been made in applying these approaches, thus making this book a timely piece on recent research findings on the particle-matrix interface at different length scales. Features wide coverage, from polymer, to ceramics and metal-based particulate composites Structured in a logical order to cover fundamental studies, computer simulations, experimental techniques and characterization

Download or read book Effects of Fiber Coating Composition on Mechanical Behavior of Silicon Carbide Fiber Reinforced Celsian Composites written by and published by . This book was released on 1998 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ceramic Abstracts written by and published by . This book was released on 1998 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book written by סולומון בן אברהם אדרת and published by . This book was released on 1972 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: