Which material is not utilized as an abrasive ?
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Answer: A. Bakelite
Explanation
Bakelite is a thermosetting synthetic resin utilized for molded plastics and electrical insulators. It lacks the extreme hardness and crystalline structure required to function as an abrasive. Therefore, Bakelite is completely excluded from being utilized as an abrasive material. Abrasive materials must possess high hardness to grind, polish, or cut other harder surfaces. Bakelite was the first synthetic plastic made from phenol and formaldehyde condensation. Its durability makes it ideal for molded housings rather than grinding wheels or powders.
Industrial manufacturing relies on specialized abrasives like corundum for precision machining. Plastics like Bakelite revolutionized electrical engineering due to their excellent insulation properties. Selecting appropriate materials ensures tools perform their intended mechanical functions safely. Pumice is a lightweight volcanic rock frequently used as a mild abrasive in polishing. Corundum is a hard aluminum oxide mineral widely employed in grinding wheels and sandpaper. Carborundum is synthetic silicon carbide prized for its exceptional hardness and cutting ability.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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