What is the phase of iron-carbon phase diagram?

The Fe – C diagram (also called the iron – carbon phase or equilibrium diagram) is a graphic representation of the respective microstructure states of the alloy iron – carbon (Fe-C) depending on temperature and carbon content. To explain this diagram, an introduction about metal structures and pure iron must be done.

What equilibrium phases are present in the FE-C diagram?

The stable equilibrium phases of the Fe-C system at ambient pres- sure are (1) the gas, g; (2) the liquid, L; (3) bcc (~iFe); (4) fcc (yFe), or austenite; (5) bcc (~tFe), or ferrite; and (6) hexagonal (C), or graphite.

What is the phase of iron?

From 910 to 1400 °C, iron exists as a phase called austenite, or γ iron. Finally, between 1400 °C and the melting point at 1535 °C, iron exists as a phase called delta ferrite, or δ iron.

What is the effect of nickel on cast irons?

The addition of Nickel in cast iron has following effects mainly: It increases impact strength, machinability, toughness. Increases hardenability, but is least effective among hardenability agents. It helps in reducing distortion and cracks in quenching phase of heat treatment.

What are the three reactions occurs in Fe-Fe3C diagram?

Three-phase reactions that occur in Fe-Fe3C phase diagram are: 1- Eutectic – at (1147 ºC ) and (4.3 wt% C), [ L ↔ Ledeburite (γ + Fe3C)]. 2- Eutectoid – at (723 ºC) and (0.83 wt% C), [ γ ↔ Pearlite (α + Fe3C)]. 3- Peritectic – at (1493 ºC) and (0.16 wt% C), [ L + δ ↔ γ ].

What are the five individual phases in the iron cementite phase diagram?

Five phases are- α-ferrite (BCC) Fe-C solid solution, γ-austenite (FCC) Fe-C solid solution, δ -ferrite (BCC) Fe-C solid solution, Fe3C (iron carbide) or cementite – an inter- metallic compound and liquid Fe-C solution.

Is iron a BCC or FCC?

Table 1: Crystal Structure for some Metals (at room temperature)

Aluminum FCC FCC
Cadmium HCP BCC
Magnesium HCP

What is the effect of nickel on cast irons Option 1 improves corrosion resistance option 2 refines grain structure Option 3 increases hardness Option 4 stabilizes carbides?

What is the effect of Nickel on cast irons? Explanation: Addition of nickel in cast irons refines the grain structure, and has a graphitizing effect on cementite. Molybdenum and Vanadium are used to increase the hardness of cast irons, while Chromium stabilizes carbides. Copper improves the resistance to corrosion.

What is the effect of nickel on property of material?

Nickel improves the toughness and strength by refining the grain size. It also prevents scale forming on the material surface. When used with chromium, it improves the hardness, ductility, fatigue resistance and critical cooling rate.

Is the phase diagram of iron-rich iron-chromium-nickel alloy valid?

The validity of this phase diagram was confirmed by applicating the same method to other published phase diagram. The δ-γ phase equilibria of iron-rich iron-chromium-nickel alloys with 23 to 38% Cr, 7 to 22% Ni are established at temperatures between 1200 and 1350 °C.

What is the gamma phase of nickel?

The nickel base alloys contain gamma phase as a matrix. Pure nickel does not attain an abnormally large elastic modulus or small diffusivity, but the gamma phase is easily reinforced for the extremely severe temperatures and time limits. Few alloys can be employed at 0.85 Tm and for periods about 100,000 hours at lower temperatures.

Is the isothermal δ-γ transformation of iron-chromium-nickel alloys isothermal?

Quenching from ferritizing temperatures of 1350 and 1250 °C the isothermal δ-γ transformation of two iron-chromium-nickel alloys with 26.0% Cr, 6.9% Ni resp. 30.0% Cr, 7.05% Ni at temperatures between 700 and 1200 °C is studied.

What precipitate occurs in nickel-iron alloys?

This precipitate occurs in nickel-iron alloys. Nickel and niobium combine in availability of iron to produce body centered tetragonal (BCT) Ni3Nb that is coherent with gamma matrix while including extensive disparity about 2.9 %.