Immersion testing test conditions

Test method Hand immersion test Test conditions ... 

The test colorfastness to potting, ISO 10S-E09, is of importance for dyed wool as potting is one of the processes woven wool fabrics can be given before they are made up iato clothing. The procedure is similar to EOS except that the test conditions are 1 h immersion ia boiling water. 

In considering the corrosion of magnesium and its alloys it is important to examine the methods available for assessing corrosion tendencies and particularly those known as accelerated tests. Tests carried out by immersion in salt water or by spraying specimens regularly with sea-water are worthless as a means of determining the resistance of magnesium alloys under any other than the particular test conditions. Extrapolation to less corrosive conditions is not valid and even the assessment of the value of protective measures by such means is hardly possible. The reason is to be found in the fact that corrosion behaviour is directly related to the formation of insoluble... 

To limit the total porosity of the coating, checking by the Iron Solution Value (ISV) test in which samples are immersed under standard conditions in a solution of sulphuric acid, hydrogen peroxide and ammonium thiocyanate, and the amount of iron dissolved is measured... 

At the specimen surface, soft corroded layer was formed during immersion and the layer could be easily removed by wiping lightly with acetone-soaked paper and in some conditions this layer was dissolved spontaneously. The thickness of this layer was defined as corrosion depth x, and measured at various test conditions. As shown in Figure 5, corrosion depth increases linearly with time, and... 

This thin-film-composite membrane has been found to have appreciable resistance to degradation by chlorine in the feed-water. Figure 2 illustrates the effect of chlorine in tap water at different pH values. Chlorine (100 ppm) was added to the tap water in the form of sodium hypochlorite (two equivalents of hypochlorite ion per stated equivalent of chlorine). Membrane exposure to chlorine was by the so-called "static" method, in which membrane specimens were immersed in the aqueous media inside closed, dark glass jars for known periods. Specimens were then removed and tested in a reverse osmosis loop under seawater test conditions. At alkaline pH values, the FT-30 membrane showed effects of chlorine attack within four to five days. In acidic solutions (pH 1 and 5), chlorine attack was far slower. Only a one to two percent decline in salt rejection was noted, for example, after 20 days exposure to 100 ppm chlorine in water at pH 5. The FT-30 tests at pH 1 were necessarily terminated after the fourth day of exposure because the microporous polysul-fone substrate had itself become totally embrittled by chlorine attack. 

Though a standard norm or absolute reference value is not available for comparison in any of the international standard specifications and the technical and research publications with respect to the chemical resistance properties of rubber, liquid immersion tests certainly provide relative and useful data with which the suitability of anticorrosive rubber lining compounds can be assessed with a fair degree of accuracy. For this reason manufacturers and applicators of rubber lining resort to tests under simulated conditions instead of accelerated ageing immersion or swelling tests. 

The above specifications give different temperature conditions for the liquid immersion test as follows ... 

The various conditions of static immersed tests and rubbed test differences can be expressed as follow ... 

Paye, M., Gomes, G., Zerweg, Ch., Pierard, G.E., and Grove, G.G. A hand immersion test under laboratory-controlled usage conditions a need for sensitive and controlled assessment methods. Contact Dermatitis 40, 133-138 (1999). 

The test principle is such that the extraction of migratable substances from a sample of the plastics is determined as the mass of non-volatile residue after evaporation of the solvent following immersion. Test specimens of at least 1 dm2 (single side considered) are immersed in the extraction solvent at the specified test conditions and then... 

Volatile test media are used up to a maximum temperature of 60 °C. It is a precondition for substitution testing that the material or article should withstand the test conditions applied with simulants D. Immerse a test specimen in olive oil in the appropriate conditions. If the physical properties are changed (e.g. melting or deformation), the material is considered to be unsuitable for use at that temperature. If the physical properties are not changed, carry out substitution tests using new specimens. 

Media considerations. SCC tests can be divided into those conducted in natural environments, such as atmospheric exposure tests and seawater immersion tests, and those which are conducted under laboratory conditions or other fabricating operations. The principal disadvantage of atmospheric exposure tests is the comparatively long time required for their completion however, they are reliable since they can reflect the projected use. There is a standard practice for evaluating stress-corrosion cracking resistance of metals and alloys by alternate immersion in a solution of NaCl 3.5%, pH 6.5. For spray testing, ASTM B-117, 2003 states the relevant conditions for conducting the test. (ASTM G44)4... 

Part 1 of ENl 186 describes the basic rules for the following choosing the most appropriate mode of test how the plastic specimen is brought into contact with the food simulant (e.g. by total immersion, in a cell or pouch, filling a plastic article) the most appropriate test conditions to use. After... 

Corrosion tests have inevitable limitations in their capacities to mimic actual service conditions of equipment. Standard, ambient pressure, immersion test procedures, with intermittent fluid refreshment, are available for both metallic and nonmetallic materials, but are limited to the ambient pressure boiling point of the fluid, and provide limited scope to simulate the effects of stress, geometry, heat transfer, and fluid flow. Such fesf procedures can be conducted at plant pressures and temperatures in autoclaves, and can be upgraded to focus on specific factors such as fluid flow and heat transfer. Even so a laboratory test, however elaborate, is a poor substitute for a test in the plant itself. 

Print adhesion on plastics (and foil) is normally checked using a self-adhesive tape peel test. A few inches of a suitable standard tape is firmly pressed onto the print area then pulled off, slowly at first, then more rapidly. An assessment of print adhesion can be made from the quantity (ideally none) removed. Adhesion can vary according to the type and colour of the ink, the degree of pretreatment, the surface involved and the printing process, etc. In order to test print under likely use conditions, product immersion tests may be necessary 60°C (140°F) is a frequently used condition, for 3 to 6 h. If product-pack may be used with soapy hands, a solution of soap can be employed. A print adhesion test, as above, can then be carried out, on the washed material, after it has been cooled to room temperature. 

Two 3" by 1/2" by 1/4" specimens of each board was tested after 7 days of underwater submersion. Prior to immersion, specimens were conditioned by oven drying at 105°C and then cooled in a desiccator. Boards were provided by manufacturers for testing. The order of materials in the table is from the lowest to the highest value of water absorption and does not indicate the particular manufacturer. 

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