ASTM C773 Compressive Strength of Fired Whiteware Materials

Scope:

ASTM C773 is used to select whiteware materials for the manufacturing of products. It is important to know the strength of the Whitewares for quality control and the selection process. Whitewares include a lot of different products—dinnerwares, sinks, toilets, dental implants.

Procedure:

There are two procedures available in ASTM C773 for the measure of compressive strength. Procedure A for ceramics of low to moderate strength, and Procedure B for ceramics of high strength. The sample is first checked for flaws. Sample with visible cracks are discarded. The sample is dye-checked to detect any flaws on its surface. The sample is immersed in an ultrasonic bath filled with hot detergent for cleaning. It is then taken out, rinsed with hot water, dried, and cooled to room temperature in a desiccator. Flawless, cleaned, and dried samples are placed in the testing machine between the contact blocks. The machine applies continuous load on the sample until the sample breaks. 

Specimen Size:

The sample must be cylindrical. It may be cut from whiteware or manufactured for the test. At least ten such samples must be provided. And they should be smaller than 80 % of the capacity of the testing machine.

Result:

The compressive strength of each specimen is calculated as follows:

C = P/A 

Where: 
C = The compressive strength of the specimen.
P = Total load on the specimen at failure.
A = Area of the bearing surface of the samp