Ash Content test determines if a material is filled with other substances. Another objective of the test is to determine the total filler content. Nevertheless, without performing additional test procedures, it cannot identify different percentages in multi-filled materials. Ash Content ASTM D2584, D5630 is unable to identify the percent carbon fiber or percent carbon black because carbon burns off during the test.
Ash Content Test Procedure:
The Ash Content test starts with taking a known amount of sample, placing the weighted sample into a pre-weighed, dry ceramic crucible made up of porcelain. This is followed by heating the crucible more than 500 °C that burns the polymer in an air atmosphere and subsequent cooling of the crucible in a desiccator to attain room temperature. The Ash residue in the crucible is considered as a filler unless the residue is less than 1%. A residue of less than 1% is mainly attributable to the additives that did not burn off.
Video 01: Determination of ash content
Six grams of a sample is divided equally among three crucibles. Two grams of the sample are placed in each crucible. An average of three crucibles is examned for the final calculation. It is possible to use smaller sample sizes; however, using smaller sample sizes may give inaccurate results.
The result of the Ash test is given in terms of % ash. To identify whether the ash is glass, mineral, or a combination of both, an intensified optical examination of the ash remainder is performed. The total ash content is equal to the weight of the ash divided by the weight of the main sample and multiplied by 100%.