Accession Number:

ADA622804

Title:

Computer Modeling of Ceramic Boride Composites

Descriptive Note:

Final rept. 1 Nov 2011-31 Oct 2014

Corporate Author:

FRANTCEVYCH INST FOR PROBLEMS OF MATERIALS SCIENCE KIEV (UKRAINE)

Personal Author(s):

Report Date:

2014-11-01

Pagination or Media Count:

187.0

Abstract:

This effort was to investigate regularities and mechanisms of kinetics growth of boride-boride composites of eutectic cocrystallization by means of computer modeling. In terms of projects scope of work a lot of new important results were obtained. Calculations showed that coefficients of thermal expansion CTE for LaB6 and systems LaB6 MeB2 Me Zr, Ti have an jump in temperature interval from 750 K to 1000 K. At elevation of temperature the energy of contact surface in these systems decreases however the system preserves its mechanical properties up to melting temperatures. Ideal work of adhesion of the interface 001-LaB6001-TixZr1-xB2, 110-LaB6110-TixZr1-xB2 increases if titanium concentration elevates. Change of a direction of fibers growth at directed solidification of eutectics LaB6 TixZr1 xB2 is associated with a big loss in energy at formation of semi-coherent interface as titanium concentration increases. A conception of internal energy sources allocated on interfaces and in phase volume of composites and is the bond energy among composites components in a solid state surface energy of interfaces, spot defects, internal stresses governed by components CTE, etc. is proposed. A new model of interface evolution at heating where a surface boundary between phases turns into a boundary with a thickness i.e. volumetric and consists of two solid parts with a liquid between is presented. Computer software to obtain multi-fractal characteristics of 2D images obtained in electron microscope is developed. A package of computer programs for 2D imitative modeling of formation of eutectic structures is developed on the base of cellular automates. Moreover the analytical review of both a retrospective and current Russian and Ukrainian papers in the field of new materials for aviation is carried out. The results obtained under this project are published in 21 papers, one monograph is also submitted to print 17 papers are presented at conferences.

Subject Categories:

  • Inorganic Chemistry
  • Ceramics, Refractories and Glass
  • Laminates and Composite Materials
  • Computer Programming and Software
  • Mechanics
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE