hardening

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just keep some basic in mind, its give u enough information about this topic.

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hardening

  1. 1. Hardening
  2. 2. • Steels can be heat treated to high hardness and strength levels. The reasons for doing this are obvious. Structural components subjected to high operating stress need the high strength of a hardened structure. Similarly, tools such as dies, knives, cutting devices, and forming devices need a hardened structure to resist wear and deformation. • As-quenched hardened steels are so brittle that even slight impacts may cause fracture. Tempering is a heat treatment that reduces the brittleness of a steel without significantly lowering its hardness and strength. All hardened steels must be tempered before use.
  3. 3. Quenching Media Four commonly used quenching media: • Brine – the fastest cooling rate • Water – moderate cooling rate • Oil – slowest cooling rate • Gas – used in automatic furnaces, usually liquid nitrogen, can be very fast cooling. Too rapid cooling can cause cracking in complex and heavy sections.

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