Casting Rate Test for Ceramic Slip: Methods & Analysis

Casting Rate Test for Ceramic Slip: Methods & Analysis

Overview

The casting rate test is conducted for clay slurry and slip. This rate is influenced by factors such as density, thixotropy, particle size distribution, and the ratio of plastic to non-plastic materials in the slurry, as well as the condition of the mould.

Importance for Sanitaryware

For sanitaryware, a high casting rate with good runoff slip properties is desirable while maintaining the other necessary properties of the body. If the density, thixotropy, particle size, and non-plastic material content in the slip are high, the casting rate will also be high.

Test Procedure

A bowl-shaped mould is used to check the casting rate. Follow these steps:

1. Clean the mould with a wet sponge

2. Pour the slip into the mould

3. Allow the slip to cast for one hour

4. Drain the slip from the mould after one hour

5. Wait 30 minutes, then cut the cast piece

6. Measure the thickness with a Vernier caliper

7. Determine hardness of the cast piece using a durometer (optional)

Key Measurements

The thickness of the cast piece indicates the casting rate of the slip. Additionally, the hardness of the cast piece can be determined using a durometer.

Testing Timeline

The testing time can vary based on the slip's properties. The drying time is typically half of the casting time.