Immersion testing types

Our goals in designing the immersion testing system were (i) to emulate or improve upon operations as specified in the manual immersion test method, (ii) to increase sample throughput, (iii) to improve the precision and accuracy of measurements, (iv) to establish procedures for testing materials in hazardous liquids, and (v) to provide sufficient flexibility to handle different types of specimens and enable future expansion of operations. 

If is equal to or greater than the pitting potential E n, both pitting and crevice-type attack are likely to occur on the specimen in an immersion test. 

If Eoorr is less than Epit, pitting-type attack of the specimen is unlikely in an immersion test. 

If the repassivation potential E is greater than Eoo , crevice-type attack is possible in an immersion test. 

NY66 and GFNY66 specimens of both test types were immersed in aq. EG solution (50/50 v/v ratio) heated at 108°C as well as in 15 wt% aq. CaCl2 solution at room temperature (20°C) and at 70°C for a period of 312 h, 600 h and 1000 h. The treated specimens were characterized by ATR-IR, GPC, tensile and impact tests. 

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. 

Coating type Immersion test (test period 240 h) Galvanic current (measurement lest period 48 h) ... 

If Ecorr is equal to or larger than Erepass> crevice-type attack is probably in an immersion test. 

Because a Type C package may be immersed in a lake, inland sea, or on the continental shelf where recovery is possible, the enhanced immersion test is required for all Type C packages regardless of the total activity in the package. 

Enhanced water immersion test for Type B(U) and Type B(M) packages containing more than 10 Aj and Type C packages... 

ABSTRACT Type of collapsibility of site is an important content in evaluation of loess collapsibility, the results calculated according to indoor test is often contradict with field test results. In order to solve the contradiction, the paper analyzes the factors that brings about difference in indoor and field test results based on the in-situ immersion test results in loess site completed in recent years, makes a study of the influence of discontinuous distribution of collapsible loess on collapse settlement, and presents the improved empirical formula for collapse settlement calculation under overburden pressure. The results show that indoor collapsibility test succeeds but impairs the correlation between factors such as loess property, stratum configuration, stress history, buried depth and settlement by immersion, during collapse settlement calculation, the correction of these influential factors shall be taken into consideration the standard used for judgment of loess as to whether it is collapsible may be properly heightened, in case of discontinuous distribution of collapsible loess, stress redistribution effect shall be taken into account. 

It is worth mentioning that at 0.6 M NaCI concentration for 46 days, the corrosion rate for CS and WS were of 3l00 xm per year and 3686 xm per year, respectively. For comparison purposes, it is possible to see that the performance of both steels in such aggressive environments of high chloride content is very poor, but it is even three to five times worse than in the case of total immersion tests. These corrosion rates seem to be inversely related to the iron conversion factor, which is lower (about 0.21) in the immersion tests than in the dry-wet tests (about 0.80). The different behaviors should be related to the type of iron phases, their characteristics, and their relative amounts. 

The type of laboratory immersion test to be used will be determined mostly by the environmental conditions that are to be simulated. For example, if the equipment is immersed in service, then the test specimens should be immersed in the laboratory test if the exposure is alternating immersion and atmospheric exposure, then a cyclic exposure test to wet/dry conditions should be used. Another determining factor is the duration of exposure for arriving at the desired results, which is associated with the degree of acceleration that will be required of the test method. 

Besides the full immersion test, there are several variations that could be used to accentuate certain types of exposure conditions. For example, the test specimen can be partially immersed in an electrolyte (liquid or solid) to create an oxygen concentration cell at the vapor-liquid/solid interface (as opposed to an occluded cell). 

While many laboratory tests for resistance of metals to stress corrosion cracking have been developed, only a few tests are amenable to actual in-situ testing in seawater. These primarily consist of the exposure of statically stressed type test specimens such as described in ASTM G 30, G 38, G 39, and ISO 7539-2, ISO 7539-3, and ISO 7539-5. In addition, welded specimens such as described in ASTM G 58 are excellent for evaluation of the stress corrosion resistance of weldments in simple immersion tests. Evaluation of corrosion fatigue is usually limited to laboratory testing. 

Immersion Tests—Continuous total immersion tests were developed more recently to provide simpler, rapid, and more reproducible test methods than the salt spray tests. Although plain sodium chloride solutions do not cause exfoliation during the desirable short periods of immersion, formulations of chloride-nitrate solutions were found that produced severe exfoliation of highly susceptible alloys of various types in only one to four days. Optimum test conditions differed for separate alloy families [J]. 

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