What loads are generally used in the Rockwell C test?

The correct answer involves using a specific combination of minor and major loads in the Rockwell C test, which is designed to measure hardness in materials. In the Rockwell C hardness testing method, the minor load is typically set to 10 kg, and the major load is applied at 60 kg. This combination is standard for testing harder materials, such as metals, as it allows for a significant indentation, providing a reliable measurement of the material's hardness.

The 10 kg minor load is first applied to seat the indenter in the material, ensuring accurate readings, followed by the application of the 60 kg major load, which creates the actual indentation where the hardness is measured. The difference in depth between the minor and major loads is then used to determine the Rockwell hardness value.

Understanding the significance of the specific loads helps in ensuring the test's consistency and accuracy across different materials.