Accession Number : ADA327203

Title :   Nanocrystalline Processing and Interface Engineering of Si3N4-Based Nanocomposites.

Descriptive Note : Progress rept. 1 Apr-30 Jun 97,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMICAL ENGINEERING

Personal Author(s) : Ying, Jackie Y.

PDF Url : ADA327203

Report Date : JUL 1997

Pagination or Media Count : 7

Abstract : With careful powder handling procedures and processing, the nanocrystalline TiN produced in our novel reactor undergoes tremendous sintering and densification to produce dense (99%) TiN materials at 1400 deg C in a simple, pressureless sintering process. This report outlines the determination of mechanical properties of these materials and contains a benchmark comparison of these properties, and the processing required to achieve them, against other TiN materials reported in the literature. The nanostructured TiN materials processed via the pressureless sintering process had a H sub v hardness value of 23.2 + or - 1.9 GPa, among the highest recorded in the literature for TiN, and a K sub c fracture toughness of 4.0 + or - 0.2 MPa . m(exp 1/2) . These sintering and property results are particularly noteworthy in comparison to those noted previously in the literature due to the complicated processing conditions required by other researchers utilizing lower quality starting powders.

Descriptors :   *INTERFACES, *COMPOSITE MATERIALS, *CRYSTALS, *ENGINEERING, *SILICON NITRIDES, DENSITY, MECHANICAL PROPERTIES, MATERIALS, POWDERS, PROCESSING, PRESSURE, TITANIUM, SINTERING, REACTOR OPERATION.

Subject Categories : Inorganic Chemistry
      Properties of Metals and Alloys
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE