文档介绍：Electrodeposition and Surface Treatment, 2 434
(1973/74) 419 - 419
@ Elsevier Sequoia ., Lausanne - Printed in Switzerland
VAPOR DEPOSITION OF COBALT-TUNGSTEN ALLOYS
J. G. DONALDSON
Rolla Metallurgy Research Center, Bureau of Mines, . Department of the Interior,
Rolla, MO. 65401 (.)
(Accepted December 6, 1973)
Summary
Cobalt-tungsten binary deposits were formed in laboratory experiments
by hydrogen reduction of the anhydrous mixed vapors of cobaltous chloride
and tungsten hexachloride. The materials were sublimed in separately heated
zones of a reaction tube and were transported in a stream of purified helium
into the deposition section of the tube where the chloride gases were reduced
to metal by a countercurrent flow of hydrogen.
Heat-treating of the near stoichiometric binary metallic deposits con-
verted nearly all to the intermetallic compound CosW; however, small quanti-
ties of both cobalt and tungsten remained. Mechanical tests showed that the
tensile strength of heat-treated 75% cobalt-25% tungsten deposits was twice
as high as that of similarly treated deposits of cobalt.
Introduction
Research on the vapor-deposition process as a means of producing pure
metals or of coating various substrates with pure metals has been conducted
by the Bureau of Mines [l - 31; other investigators have also been active in
this field [4, 51. Successful solution of problems associated with this activity
prompted an investigation of the feasibility of producing binary materials by
a similar process. The procedures used to produce cobalt-tungsten binary de-
posits by hydrogen coreduction of the vaporized halides of these metals are
described in this report, and some of the properties of the deposits are dis-
cussed.
As a means of metal transfer, chemical vapor deposition has a fairly lo