Millwright Level 1 Practice Exam

Are cemented carbides sharpened on aluminum oxide wheels?

1. Yes, they are

2. No, they are not

3. Only under specific conditions

4. Only with specific machines

The correct answer is: No, they are not

Cemented carbides are not typically sharpened on aluminum oxide wheels due to their hard and brittle nature. Cemented carbides, which are made from the combination of tungsten carbide and cobalt, have a much higher hardness compared to aluminum oxide. Aluminum oxide wheels are designed primarily for use with softer materials, and using them on cemented carbide can lead to significant wear on the wheel itself rather than effectively sharpening the carbide tool. Instead, diamond wheels are generally used for sharpening cemented carbide because they possess a hardness that is suitable for grinding such tough materials. This ensures that the sharpening process will be effective, maintaining the integrity and cutting edge of the carbide without damaging the tool or the grinding medium. In essence, the hardness disparity between aluminum oxide wheels and cemented carbides makes sharpening with aluminum oxide impractical, which is why the correct response indicates that cemented carbides are not sharpened on aluminum oxide wheels.