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MIL-C-11796B <br /> 4.6.8.5 Corrosiveness. while still hot, the compound and any loose- <br /> corrosion products shall be removed by swab- <br /> 4.6.8.5.1 Test specimens. The corrosiveness bing with naphtha, followed by methanol, <br /> test shall be conducted with 1 by 2 by 1/4 inch using surgical-gauze or absorbent-cotton <br /> specimens conforming to the following: pads. Each swabbing operation shall be fol- <br /> (a) Brass, composition 1, Specification lowed by rinsing with clean portions of' <br /> QQ-B-613 naphtha and methanol successively. Air dry <br /> the specimens and weigh them accurately. <br /> (b) Cadmium, Specification QQ-A-671 Calculate their weight loss in terms of milli- <br /> (c) Zinc, Specification QQ-Z-285 grams per square centimeter of specimen <br /> surface. <br /> (d) Magnesium, Specification QQ-M-44 <br /> 4.6.8.5.3.1 The weighed lead specimen shall <br /> (e) Aluminum, condition T, Specifica- be covered separately with approximately 50 <br /> tion QQ-A-355 grams of compound which has been heated <br /> (f) Steel, Specification QQ-S-640 to 180° ± 3° F. prior to use in the test. A <br /> (g) Lead, Grade A, Specification QQ- suitable glass container, such as a test tube, <br /> L-201 shall be used for holding the lead specimen <br /> and the molten compound. The lead specimen <br /> shall be subjected to the same oven test as <br /> 4.6.8.5.2 Preparation of test specimens. the other specimens, and its weight loss like- <br /> The specimens shall be polished to remove wise determined. <br /> pits, burrs and irregularities from the faces <br /> and edges, finishing with a 240 grit polishing 4.6.8.6 Stain (Class 3 only). <br /> medium. The specimen shall be held in a •.�' <br /> suitable holder to avoid contact with the 4.6.8.6.1 Test panels. Six test panels shall <br /> hands. After polishing, the specimens shall be cleaned and polished in accordance with <br /> be cleaned by swabbing in hot naphtha and 4.6.8.1 for this test. <br /> a final rinse in warm methanol. The rimeth- <br /> anol should be diluted with approximately 5 4.6.8.6.2 Water emulsions. A 5-percent and <br /> parts by volume of distilled water for use a 16-percent water emulsion of the compound <br /> in rinsing the magnesium specimens. shall be prepared by heating 95 and 85 <br /> grams, respectively, of the compound until <br /> 4.6.8.5.3 Test procedure. Weigh the pol- molten, and adding 5 ml and 15 ml of dis- <br /> ished and cleaned specimens accurately and, tilled water, respectively, to the molten sam- <br /> with the exception of the lead specimen (see ples. The compound-water mixtures shall <br /> 4.6.8.5.3.1), stand them on end around the then be emulsified by means of a mechanical <br /> inner perimeter of a wide-mouth jar, ap- stirrer until a homogenous mass is formed. <br /> proximately 3 inches in diameter, and having <br /> a tight-fitting screw cap. The specimens shall 4.6.8.6.3 Test procedure. Coat the polished <br /> be placed clockwise in the order in which surfaces of two of the panels with the origi- <br /> they are listed in 4.6.8.5.1, using glass sepa- nal compound (set No. 1), of two other <br /> rators between them, if necessary. Cover the panels with the 5-percent emulsion (set No. <br /> specimens with approximately 300 ml. of 2), and of the remaining two panels with <br /> the compound, heated to 180° ±3° F. prior the 15-percent emulsion (set No. 3), with <br /> to use in the test. Seal the jar tightly, and the coating in each instance being approxi <br /> place it for 14 days in an oven maintained at mately 5 mils in thickness. Assemble the two <br /> 1800 ± 3° F. At the end of this period the coated panels of each set so that the coated <br /> specimens shall be removed firom the jar and, surfaces face each other in a sandwich-like <br /> 8 <br /> I <br /> i <br />