Which hardness test is described as inexpensive and non-destructive and uses a relatively softer indenter?

• A. Rockwell hardness test
• B. Vickers hardness test
• C. Brinell hardness test
• D. Knoop hardness test

Answer: (A)

The test described emphasizes practicality: it’s quick, inexpensive, and leaves only a small, shallow imprint, which keeps surface damage to a minimum. The Rockwell hardness test achieves this by using a simple setup and a relatively shallow indentation read directly from the machine. On many scales, the indenter is a steel ball, which is softer than the diamond or pyramid indenters used in the other methods. Because you don’t need microscopic measurement and you can obtain results rapidly with a lightweight apparatus, it’s economical and tends to be non-destructive for typical metal samples. In contrast, Vickers and Knoop rely on diamond indenters and require precise optical measurements, adding cost and time; Brinell uses a larger ball and heavier load, leaving a more noticeable mark that can be considered more damaging for some parts. This combination of simplicity, speed, low cost, and a relatively softer indenter makes the Rockwell test the best match for the description.