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metallization, details get a number of valuable properties, for example, heat
resistance, resistance to scaling, etc.
Diffusive metallization can be carried out:
- in the firm environment. metallizator is ferroalloy (ferrochrome, ferrosilicium,
etc.) with addition of chloride ammonium.
- in the melted metal with a low temperature of melting (zinc, aluminum) which
is carried out by the detail immersion to fusion.,
- in the gas environment containing chlorides of various metals. At firm and gas
metallization, saturation happens to the help of flying compounds of chlorine
with metal which at 1000-1100ºС enter exchange reaction with iron with
formation of active diffusing atom of metal.
Alitizing is a process of diffusive saturation of a blanket by aluminum. It is
carried out in powdery mixes or melted aluminum. Thickness of an aluminized
layer makes 0,2-1mm, concentration of aluminum in it to 30%. Alitizing is
applied to increase of corrosion resistance and heat resistance of details from
carbonaceous steel, working at high temperature.
Chromium plating is a process of diffusive saturation of a surface by chrome.
Thickness of a layer makes 0,2mm. Chromium plating is used for products from
steel of any brands. At chromium plating, high firmness against gas corrosion to
800ºС, a resistance to scaling and wear resistance of details in hostile
environment (sea water, acids) is provided).
Siliconizing is a process of diffusive saturation of a surface by silicon.
Thickness of a layer is 0,3-1mm. Along with the increased wear resistance,
siliconizing provides high corrosion resistance of steel products in acids and sea
water. It is applied to the details used in chemical and oil industry.
Borating is a process of diffusive saturation of a surface by boron. Thickness
of borated layer reaches 0,4mm. Borating gives to a blanket exclusively high
hardness, wear resistance and stability against corrosion in various
environments.
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