Metal Powders, Sieve Analysis

As described above, a number of empirical and analytical correlations for droplet sizes have been established for normal liquids. These correlations are applicable mainly to atomizer designs, and operation conditions under which they were derived, and hold for fairly narrow variations of geometry and process parameters. In contrast, correlations for droplet sizes of liquid metals/alloys available in published literature 318]f323ff328]- 3311 [485]-[487] are relatively limited, and most of these correlations fail to provide quantitative information on mechanisms of droplet formation. Many of the empirical correlations for metal droplet sizes have been derived from off-line measurements of solidified particles (powders), mainly sieve analysis. In addition, the validity of the published correlations needs to be examined for a wide range of process conditions in different applications. Reviews of mathematical models and correlations for... 

Sieve Analysis Determine as directed under Sieve Analysis of Granular Metal Powders, Appendix EC. 

Mercury Determine as directed in the monograph for Iron, Reduced, but use 2 g of sample and 40 mL of Sodium Citrate Solution in preparing the Sample Solution, and prepare the Diluted Standard Mercury Solution as follows Transfer 4.0 mL of Mercury Stock Solution into a 250-mL volumetric flask, dilute to volume with 1 N hydrochloric acid, and mix (1 mL = 4 ig of Hg). Modify the first sentence of the Procedure to read Prepare a control by treating 1.0 mL of Diluted Standard Mercury Solution (4 p,g Hg) in the same manner. Sieve Analysis Determine as directed under Sieve Analysis of Granular Metal Powders, Appendix IIC. 

As well as these, several industries have their own specifications aggregates [22], porcelain [23], ceramic powders [24], plastics [25], coating powders [26], concrete [27] and metals [28], The standard for glass spheres [29] is designed specifically for sieve analysis of glass spheres used in reflective road and pavement markings and other industrial uses. 

ASTM C285-88 (Re-approved 1994) Standard test method for sieve analysis of wet milled and dry milled porcelain enamel, for determination of the fineness of frit in wet-or dry-milled porcelain enamels and other ceramic coatings on metals by use of the number 200 or No 325 mesh, 212 ASTM C925-79 (Re-approved 1995) Standard test method for precision electroformed wet sieve analysis of non-plastic ceramic powders, for particle size distribution determination ofpulverized alumina and quartz for particle sizes from 45 pm to 5 pm by wet sieving, 212, 230... 

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