Standard Test Method for Workability Index of Fireclay and High-Alumina Refractory Plastics
The workability/consistency of as-received material is determined. Cylindrical specimens are impacted under a 14-lb. load and the percent deformation is reported. The testing of five specimens is recommended by ASTM. A 10 lb. representative sample should be submitted, including the production date for the material.
Workability index serves as a measure of the facility with which refractory plastic materials can be rammed, gunned, or vibrated into place.
Workability index is commonly used to control consistency of plastics during manufacture. It has also been found useful for specification acceptance by the consumer.
The workability index determination can provide information for developing a plastic body. When a sample splits under impact at various water contents, it is an indication that the material is "short or lacking in plasticity.
Determinations on samples that split during impact will be difficult to reproduce. If the sample splits, the measurement is not a true indication of deformation. This should be noted in the report.
1.1 This test method covers the determination of the workability index of fireclay and high-alumina refractory plastics by measuring the plastic deformation of a molded test specimen when subjected to impacts.
Extracted, with permission, from ASTM C181 Standard Test Method for Workability Index of Fireclay and High-Alumina Refractory Plastics, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the standard may be purchased from ASTM International, phone 610-832-9555, e-mail: firstname.lastname@example.org, website: www.astm.org.
Fulfilling the directive of our founder and benefactor, the Edward Orton Jr. Ceramic Foundation deploys its profits to support studies and research at the university level to promote and advance the science of materials processing.