Magnesium alloys cleaning

COALCONVERSIONPROCESSES - CLEANING AND DESULFURIZATION] (Vol 6) -in presence of magnesium pAGNESIUM AND MAGNESIUM ALLOYS] (Vol 15)... 

To detect aluminum in alloys of aluminum and magnesium, the cleaned surface of the sample is tested for 1-2 minutes with one drop of cone, hydrochloric acid and the solution, diluted with water (1.5-2 ml), is evaporated to dryness in a porcelain dish. The residue is treated with three drops of 0.005 % Arsenazo I solution and finally with eight drops of 25 % hexamine solution. A change in color from red to violet indicates the presence of... 

If the atmosphere is clean but not dry and the humidity approaches 100%, a scattered pattern of corrosion spots eventually appears, but considerable areas of unaffected surface remain for a very long time. If, however, the surface becomes contaminated by corrosive dust or cathodic particles, the whole surface rapidly becomes covered with a grayish layer of corrosion product (Tawil, 1987). A clean, unprotected magnesium alloy surface exposed to indoor or outdoor atmospheres free from salt spray develops a gray Him that protects the metal from corrosion (Froats et al., 1987). The rates of corrosion and resistance to corrosion of magnesium alloys vary depending on alloy composition (Loose, 1946) as discussed previously. 

SFfi/ inert gas mixtures are used in the production of magnesium and magnesium alloys and the cleaning of aluminium melts. It functions as a protective gas to prevent ignition, oxidation and nitride formation as well as for removing oxides and solid inclusions. 

Uses Low foaming alkaline cleaner for nonferrous metals for spray cleaning of copper, aluminum alloy, brass, magnesium alloy, etc. 

Table 4.20 The more usual cleaning and chromating processes for magnesium-base alloys ...

Violent decomposition, with evolution of hydrogen chloride, may occur when 1,1,1-trichloroethane comes into contact with aluminium or its alloys with magnesium [10]. Aluminium-dusty overalls were cleaned by immersion in trichloroethylene. During subsequent drying, violent ignition occurred. This was attributed to presence of free... 

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