Protective coats
Protective coats from precious metals
Existing industrial technologies of coats from gold and other precious metals are based on the application of the electrolytic methods of precipitation, which have a number of disadvantages. Main ones from them are insufficient adhesion of coats and a high toxicity of used chemical agents that represents the dangerous for the staff and the environment. There are also problems in reproduction of natural color of metals in coatings.
The original technology of magnetron
coatication of high-quality coatings from precious metals on metallic
and non-metallic wares of a wide application has been designed in the
laboratory of IPT INP. The process of coating precipitation takes place
in vacuum that is why the rich color tints of precious metals and
brilliance of polished wares is fully kept. Magnetron precipitation of
precious metals does not use unsuitable in application toxic chemical
solutions.
Coatings have a higher resistance to wear as a result of dispersing
reinforcement of precipitated layer by microaddings of chrome, iron and
other elements. Coating thickness and consumption of precious metals is
easily controlled.
In the production cycle irrevocable loses of precious metals are
absent. A part of pulverized metals, which accumulates inside the
camera and not on wares, is easily gathered and with target remains
used repeatedly for new target manufacturing for magnetron.
The highly productive industrial vacuum magnetron facility for coatication of coatings from precious metals has been designed and manufactured. There have been carried out 3-4 cycles of coatication of coatings 2-3 mkm in thickness on the facility without target replacement. One cycle of precipitation beginning from ware loading into the camera to their unloading lasts 2.5-3 hours depending upon coating thickness.
Maximal total acres of ware surface in
a one cycle (loading) are 500 cm2. It is possible to place
36 wares in the form of a disk 4 cm in diameter for two-sided
coatication of coatings in the camera 20 dm2 in volume on six object
posts with planetary rotation. All object posts have a form of
trihedral prism.
The received technological results can be applied on mints, industrial
enterprises for manufacturing jewellery, common and other wares with
coating from precious metals.
On the plant of non-ferrous metals (Ust-Kamenogorsk, Kazakhstan) the technological line of magnetron coating precipitation from precious metals on wares of governmental demand has been working beginning with 1994. Experience work in the industry showed the absence of precious metal loses and also high technical and decorative qualities of coatings and reliability of designed technique.
Protective coats from titanium nitride
A high solidity and good decorative qualities of coatings from titanium nitride promote to their using in the industry on plants for manufacturing medical, domestic wares and instruments (fig. 8).
Fig.8 Decorative coatings from titanium nitride
Existing plasma technologies of coating receiving from titanium nitride do not provide the necessary decorative and protective qualities of wares. Coatication of coatings is accompanied with heating of processed wares up to a high temperature (600oC) and worsening of the qualities of ware material.
Elaborated ion-plasma technology and corresponding magnetron equipment allowed improving a visual perception of coatings from titanium nitride. The coating is synthesized and precipitated at titanium target dispersion in working gas, which containes nitrogen.
The coatings are biologically compatible with tissues of human organism and during a number of years keep a brilliance of polished wares and have a different solution with colored tints of known alloys of gold.
Protective coats from titanium nitride on tool steel and other wares have a controlled stochiometric solution when it is necessary to realize a maximal solidity of titanium nitride. Original productive magnetron pulverizes provide a good adhesion of coatings with ware surface. A high solidity of coatings from titanium nitride gives them steadiness to wear and increases durability of wares. The coatication of coatings on the special instrument takes place at 150oC, that is why after process termination the qualities of hardened steel are not changed.
The highly productive industrial vacuum magnetron facility for coatication of protective coatings from titanium nitride has been designed and manufactured (fig. 1). There have been carried out 10 cycles of coatication of coatings 2 mkm in thickness on the facility without target replacement. The total acres of ware surface in one cycle (loading) are 500 cm2. Speed of coatication of coatings on wares is 2 mkm/h.
