Test methods surface finish

In rubber testing, the surface finish of metals is of importance, for example on mould surfaces and compression set plates. There are a number of standards in the ISO Geometric Product Specification series but the most relevant is ISO 428729 which covers terms, definitions and surface texture parameters relating to the profile method of measuring surface finish. There are apparently over 1000 different parameters to characterize surface finish30 but only a few are generally encountered. The most commonly found is Ra (previously called CLA) which is the mean deviation of the surface profile above and below the center line, followed by Rz, a measure of the peak to valley height. For example, the arithmetic mean deviation (Ra) of the compression plates for compression set tests must be better than 0.2 m. 

Ultrasonic Microhardness. A new microhardness test using ultrasonic vibrations has been developed and offers some advantages over conventional microhardness tests that rely on physical measurement of the remaining indentation size (6). The ultrasonic method uses the DPH diamond indenter under a constant load of 7.8 N (800 gf) or less. The hardness number is derived from a comparison of the natural frequency of the diamond indenter when free or loaded. Knowledge of the modulus of elasticity of the material under test and a smooth surface finish is required. The technique is fast and direct-reading, making it useful for production testing of similarly shaped parts. 

The first draft (finished in 1993 and revised in 1995) describes a test method for determination of the bactericidal activity of a chemical disinfectant applied to a contaminated surface under laboratory conditions ... 

An important QC analysis in the fibre and textile industry is the surface finish determination by Soxhlet extraction (AATCC Test Method 94-1992). Solvent extraction is used on textile materials to determine naturally occurring oily and waxy materials that have not been completely removed from the fibres (ASTM Method D 2257-96). Meanwhile, environmental, safety... 

Experimental methods exist to determine a critical value for any one of these factors when the others are held constant. However, parameters such as pH, concentration of inhibiting ions (e.g., SO4"), dissolved gas, test area, flow rate, and surface finish influence the resistance to pitting. ... 

In a search for reliable accelerated test methods for determining coating performance, electrochemical techniques have often been explored. The corrosion resistance of a coated steel panel is a composite of the steel quality, its surface finish and the quality of the coating. For this reason. Bonderite 40 coated steel panels were included in our work. They were employed primarily to aid in the interpretation of the electrical measurements for the nitrile-based photocured samples. 

ASTM E 1317 Standard Test Method for Flammability of Marine Surface Finishes. Annual Book of Standards, Vol. 04.07, ASTM International, West Conshohocken, PA. 

The slope of the linear part and the incubation time are very dependent on hardness, grain structure, purity, mechanical fatigue strength, surface finish, and conditions of the eroded material. All these parameters should be carefully monitored in order to obtain reproducible results which was also necessary in dosimetry methods described above which used cleaning effects. It is, of course, inevitable that the foil used as a solid test probe will interfere with the cavitation field to some extent. Erosion rates have, however, been linearly correlated to the total noise of cavitation [125]. 

Hardwood plywood products are decorative in nature and are designed for interior use. Over 95X of all hardwood plywood is made with urea-formaldehyde adhesives. Responding to concerns about formaldehyde and certain wood products, test methods for measuring surface emissions were developed in the early 1980 s. Emissions from most hardwood plywood and particleboard products have decreased 65% to 95% in recent years primarily by use of low emitting UF adhesives and/or scavengers. Good correlation has been demonstrated between product test methods and indoor levels of formaldehyde in experimental manufactured homes. Decorative surface finishes can act to either increase or decrease surface emissions, depending on the nature of the finish and the substrate. 

Therefore, we make resistivity measurements by first generating calibration curves on known-reslstlvlty samples of the same type, orientation, and surface finish as the test specimens to be profiled. Calibration curves are generated for a particular pair of probes at a particular time, using known-reslstlvlty samples of the highest quality available. This calibration procedure Is a particularly noteworthy characteristic of the spreading resistance technique. It means that spreading resistance Is a comparison method, and that Its ultimate accuracy Is therefore limited only by the calibration material available. Fortunately, It s now possible to obtain complete sets of calibration samples from the National Bureau of Standards. 

The method consists of taking cylindrical test coupons of specified dimensions and surface finish, and suspending them in a specified volume of a specified test solution representative of a moderately aggressive supply water for a period of 24 hours. The immersions are repeated ten times using fresh test solution. Metals are determined using the extract from the final 24-hom period. 

It should be noted that most optical properties are greatly affected by the condition of the surface, so that the method of preparation of test pieces is most important and needs to be carefully controlled if comparative results are required. To obtain a very high standard of surface finish, molding against platens of borosilicate glass without a release agent has been recommended,... 

Abstract It is necessary for environmental evaluation of surface finishing processes. From the viewpoint of current environmental protection acts and laws in various countries (which seem to be getting stricter) surface finishing industries are facing serious challenges. These industries tend to release heavy metals and other pollutants into our air, water, and soil. Therefore, to meet the demands of the environmental protection laws, they will need to modify current processes and propose some new ones to replace their traditional methods. In order for these new processes to be adequate and effective, appropriate environmental evaluations are needed to test them. This chapter describes several ways to evaluate and treat harmful contaminants in air and water (especially those from the surface finishing industry). 

The ferric chloride test details ctm be modified and still fall within the spirit of the requirements of the published method. The exposure time tmd temperature ctm be filtered, as can the surface finish. As mentioned above, surface finish can have important impact on the localized corrosion behavior. For example, it can affect the geometry of occluded sites and, in some cases, it can alter the surface area for cathodic reactions. Thus, it is important that the surface finish be chosen with care to simulate the expected conditions of the application. 

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