Making Clay Test Bars

Section: Clay Bodies, Subsection: Testing

Description

Being able to make good consistent test bars and fire them in a consistent and proper way is a basic requirement of getting valid results for shrinkage and porosity measurement.

Article

The FORESIGHT Ceramic Database software defines many tests that can provide valuable information about the physical properties of clays, yet require little expensive test equipment to perform. You will probably agree knowing the chemistry of a clay material means little when compared to understanding its physical properties.

FORESIGHT test definitions are text-only and explain in detail exactly how to perform the procedures. We have tried to make-do with straight text where possible so that information can be sent via email and posted on our BBS and the Internet in a form easily used by anyone on any computer. While it is possible to describe most procedures adequately via text, I will show you two photos here that will help clarify two things in the procedure for the SHAB test (shrinkage and absorption properties) for making clay test bars.

The procedure given for stacking the bars is illustrated here. This angular stacked pattern encourages even heating of all bars compared to laying them on the kiln shelf, which acts as a heat-sink.

Notice that the three bottom bars are sawed from an insulating fire brick. The bars are piled at an angle to each other so that shrinkage has less likelihood of collapsing the stack.

A stamp of this type is very important so that all specimens can be accurately impressed with readable identification numbers and other markings as described in the FORESIGHT test procedures. •

Links to Other Items

T-41

Authors

Tony Hansen (Owner)

Much more information with complete interlinking to many related
databases can be found by logging into the www.ceramicmaterials.info database