Metallurgy Question:
What is carbide?
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Answers:
Answer #1
The epsilon carbide is transition carbide of between Fe2C and Fe3C composition, with hexagonal close packing microstructure, which forms over a range of 250-400 ºC temperature during lower-bainite transformation. This transformation happens during tempering heat treatment of quenched steels, or during slow cooling in that temperature range.
It is fine dispersed carbide in a ferrite needle-like matrix. Lower bainite has lower tensile strength (about 5-10%), but usually same hardness as martensite structures, but with a higher toughness.
The epsilon carbide is transition carbide of between Fe2C and Fe3C composition, with hexagonal close packing microstructure, which forms over a range of 250-400 ºC temperature during lower-bainite transformation. This transformation happens during tempering heat treatment of quenched steels, or during slow cooling in that temperature range.
It is fine dispersed carbide in a ferrite needle-like matrix. Lower bainite has lower tensile strength (about 5-10%), but usually same hardness as martensite structures, but with a higher toughness.
Answer #2
Carbide termed as Fe3C is the hardest microstructure in steel having carbon percentage of 6.67. There are two forms of carbides as per iron-iron carbide diagram of plane carbon one which is exist along with ferrite as alternate layers in pearlite and free carbide in steels having carbon % more than 0.8%. It is spreaded over the matrix of martensite in tool steels and high carbon steels.
Carbide termed as Fe3C is the hardest microstructure in steel having carbon percentage of 6.67. There are two forms of carbides as per iron-iron carbide diagram of plane carbon one which is exist along with ferrite as alternate layers in pearlite and free carbide in steels having carbon % more than 0.8%. It is spreaded over the matrix of martensite in tool steels and high carbon steels.