Acid copper sulphate test

The evaluation of heat treatments or the effectiveness of stabilisation by limiting carbon content of these stainless steels can be determined by subjecting specimens to the ASTM standardised acid copper sulphate test or boiling nitric acid test (ASTM A262 1986 see also Sections 9.5 and 1.3). 

Acid copper sulphate test t 16 wt.% H2SO4 -1-100 g/l CuSO, (-1- metallic copper) 72 h exposure to boiling solution 1. Appearance of sample upon bending 2. Electrical resistivity change 3. Change in tensile properties -1- 0-30 to -1- 0-58 Chromium-depleted area... 

Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 1 Corrosion test in nitric acid medium by measurement of loss of mass (Huey test) Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 2 Corrosion test in a sulphuric acid/copper sulphate medium in the presence of copper turnings (Moneypenny Strauss test)... 

Ammonium tetrathiocyanatomercurate(II)-copper sulphate test. The faintly acid (sulphuric acid or acetic acid) solution is treated with 0-1 ml 0 25m copper sulphate solution, followed by 2 ml ammonium tetrathiocyanatomercurate(II) reagent. A violet precipitate is obtained. The test is rendered still more sensitive by boiling the mixture for 1 minute, cooling and shaking with a little amyl alcohol the violet precipitate collects at the interface. Iron salts produce a red colouration this disappears when a little alkali fluoride is added. 

Ammonium tetrathiocyanatomercurate(II)-copper sulphate test Acidify the solution faintly with a few drops of m sulphuric or 2m acetic acid. Add... 

British Standard Method for Determination of Resistance to Intergranular Corrosion of A ustenltic Stainless Steels Copper sulphate-Sulphuric acid Method (Moneypenny Strauss Test) BS 5903 (1980)... 

Test methods for determining electrolytic corrosion with electrical insulating materials Method for determination of resistance to intergranular corrosion of austenitic stainless steels copper sulphate-sulphuric acid method (Moneypenny Strauss test) Specification for electroplated coatings of tin/lead alloys... 

Place a drop or two of the test solution, which is slightly acid (preferably with sulphuric acid), on a spot plate, add 1 drop 0-25m copper sulphate solution and 1 drop ammonium mercurithiocyanate reagent. A violet (or blackish-purple) precipitate appears. 

The experimental details are as follows. Treat the test solution with an equal volume of 2m sodium or potassium hydroxide (or treat the test solid directly with a few ml of the alkali hydroxide solution, warm for a few minutes with stirring and then cool), add a few drops of 0-25m copper sulphate solution (i.e. just sufficient to yield a visible precipitate of copper(II) hydroxide), shake the mixture vigorously for 5 minutes, and filter. If the filtrate is not clear, warm to coagulate the colloidal copper hydroxide and filter again. A distinct blue colouration indicates the presence of a tartrate. If a pale colouration is obtained, it is advisable to add concentrated ammonia solution dropwise when the blue colour intensifies it is perhaps better to acidify with 2m acetic acid and add potassium hexacyanoferrate(II) solution to the clear solution whereupon a reddish-brown precipitate or (with a trace of a tartrate) a red colouration is obtained. 

Colour Tests. Copper Sulphate (Method 2)—blue (1 to 2 min) Mandolin s Test—red Marquis Test—yellow Methanolic Potassium Hydroxide—yellow Sulphuric Acid—yellow. 

Colour Tests. Coniferyl Alcohol—orange Copper Sulphate (Method 1)—green Mercurous Nitrate—black Nitrous Acid— yellow. 

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