Structure and properties of braided sleeve preforms for chemical vapor infiltration

PDF Version Also Available for Download.

Description

In all composites the properties and structure of the reinforcement strongly influence the performance of the material. For some composites, however, the reinforcement also affects the fabrication process itself exerting an additional, second order influence on performance. This is the case for the chemical vapor infiltration (CVI) process for fabrication of ceramic matrix composites. In this process the matrix forms progressively as a solid deposit, first onto the fiber surfaces, then onto the previous layer of deposit, ultimately growing to fill the inter-fiber porosity. The transport of reactants to the surfaces and the evolved morphology of the matrix depend on ... continued below

Physical Description

23 p.

Creation Information

Starr, T.L.; Fiadzo, O.G. & Hablutzel, N. April 1, 1998.

Context

This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this report can be viewed below.

Who

People and organizations associated with either the creation of this report or its content.

Authors

Sponsor

Publishers

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this report. Follow the links below to find similar items on the Digital Library.

Description

In all composites the properties and structure of the reinforcement strongly influence the performance of the material. For some composites, however, the reinforcement also affects the fabrication process itself exerting an additional, second order influence on performance. This is the case for the chemical vapor infiltration (CVI) process for fabrication of ceramic matrix composites. In this process the matrix forms progressively as a solid deposit, first onto the fiber surfaces, then onto the previous layer of deposit, ultimately growing to fill the inter-fiber porosity. The transport of reactants to the surfaces and the evolved morphology of the matrix depend on the initial reinforcement structure. This structure can vary greatly and is controlled by such factors as fiber size and cross-section, the number of filaments and amount of twist per tow or yarn, and the weave or braid architecture. Often the choice of reinforcement is based on mechanical performance analysis or on the cost and availability of the material or on the temperature stability of the fiber. Given this choice, the composite densification process--CVI--must be optimized to attain a successful material. Ceramic fiber in the form of cylindrical braided sleeve is an attractive choice for fabrication of tube-form ceramic matrix composites. Multiple, concentric layers of sleeve can be placed over a tubular mandrel, compressed and fixed with a binder to form a freestanding tube preform. This fiber architecture is different than that created by layup of plain weave cloth--the material used in most previous CVI development. This report presents the results of the investigation of CVI densification of braided sleeve preforms and the evolution of their structure and transport properties during processing.

Physical Description

23 p.

Notes

OSTI as DE98052754

Source

  • Other Information: PBD: Apr 1998

Language

Item Type

Identifier

Unique identifying numbers for this report in the Digital Library or other systems.

  • Other: DE98052754
  • Report No.: ORNL/Sub--87-00184/07
  • Grant Number: AC05-84OR21400
  • DOI: 10.2172/672102 | External Link
  • Office of Scientific & Technical Information Report Number: 672102
  • Archival Resource Key: ark:/67531/metadc704787

Collections

This report is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • April 1, 1998

Added to The UNT Digital Library

  • Sept. 12, 2015, 6:31 a.m.

Description Last Updated

  • May 2, 2016, 4:14 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 5

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Starr, T.L.; Fiadzo, O.G. & Hablutzel, N. Structure and properties of braided sleeve preforms for chemical vapor infiltration, report, April 1, 1998; Tennessee. (digital.library.unt.edu/ark:/67531/metadc704787/: accessed August 16, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.