Cermets typically consist of a ceramic-to-metal ratio of 80:20. Which of the following is classified as a cermet?
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Answer: D. Tungsten carbide
Explanation
Tungsten carbide is a classic cermet material composed of hard ceramic particles. It uses a cobalt or nickel metal matrix to bond the carbide grains. The combination provides extreme hardness alongside necessary fracture toughness. Cermets combine ceramic materials for hardness with metals for toughness. Powder metallurgy techniques are used to press and sinter cermet components. The ceramic phase provides high wear resistance at elevated cutting temperatures.
Machining tools and high-wear industrial components are frequently fabricated from cermets. Tungsten carbide inserts cut metal at high speeds without losing edge sharpness. Selecting appropriate cermet grades extends tool life in demanding manufacturing environments. Zirconia is a pure ceramic material rather than a metal-ceramic composite cermet. Alumina is an oxide ceramic without a metallic bonding matrix component. Bakelite is a synthetic thermosetting polymer resin rather than a ceramic composite.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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