KINETIC STUDIES OF THE ATTACK OF REFRACTORY MATERIALS BY FLUORINE ATOMS.

Abstract

The true kinetices of the attack of molybdenum and tungsten surfacs by both atomic and diatomic fluorine were studied using microwave charge--fast flow vacuum system techniques coupled with electrical resistance heating of the reacting specimens. Experimental results are reported herein covering the surface temperature range from 700K to their respective thresholds. Exploratory kinetic data is also included for the fluorination of titanium, graphic and boron. It is shown that despite the well known reactivity of molecular fluorine, dissociation produces a striking enhancement in the Mo- or W-atom removal probability at surface temperatures corresponding to appreciable steady state adatom populations. Interestingly enough, multiple local maxima appear in the Arrhenius diagram for the F-atom attack of Mo(s) and W(s)--these maxima presumably being attributable to the formation/desorption of distinct metal fluorides of widely discrepant stoichiometry and thermodynamic stability. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1970
Accession Number
AD0703881

Entities

People

  • Daniel E. Rosner
  • H. Donald Allendorf

Tags

DTIC Thesaurus Topics

  • Advanced Materials
  • Chemical Stability
  • Electrical Resistance
  • Fluorination
  • Fluorine
  • Heat Resistant Alloys
  • Heat Resistant Materials
  • Materials
  • Metals
  • Refractory Materials
  • Refractory Metal Alloys
  • Resistance
  • Steady State
  • Surface Temperature

Fields of Study

  • Physics

Readers

  • Metallurgy
  • Molecular Photonics/Laser Physics
  • Thin Film Deposition Science.