What is the microstructure of Hypereutectoid steel?

In hypoeutectoid steel, the equilibrium microstructure at room temperature consists of ferrite and pearlite; this ferrite is called proeutectoid ferrite (Fig. 6(b)).

What is the difference between microstructure of Hypoeutectoid and Hypereutectoid?

(a) A “hypoeutectoid” steel has a carbon concentration less than the eutectoid; on the other hand, a “hypereutectoid” steel has a carbon content greater than the eutectoid. (b) For a hypoeutectoid steel, the proeutectoid ferrite is a microconstituent that formed above the eutectoid temperature.

What is a Hypereutectoid?

A hypereutectoid alloy is a metal composed of two or more metallic elements in which the concentration of solute is greater than that of the eutectoid. In steel, such alloys display lower carbon contents. Hypereutectoid alloys are corrosion resistant.

What are hypo and Hypereutectoid steels?

Hypereutectoid steel consists of pearlite and cementite at room temperature. Hypoeutectoid Steel Steel that contains less than 0.77 percent carbon. Hypoeutectoid steel consists of ferrite and pearlite at room temperature.

What is microstructure of steel?

The microstructure is predominantly martensite but also has allotriomorphic ferrite, Widmanstätten ferrite, bainite and pearlite. Notice that the spherical shape of a pearlite colony is obvious in this sample because of the lack of impingment.

What is steel and what you understand by eutectoid Hypereutectoid and hypoeutectoid steel?

Steels are generally classified by carbon content, with hypoeutectoid (below 0.77 wt. % carbon), eutectoid (at 0.77 wt. % carbon), or hypereutectoid (above 0.77 wt. % carbon) steels, each of which has a solid solution of carbon in austenite at high temperature.

What is the carbon content in Hypereutectoid steel?

Hyper-eutectoid Steel: Plain carbon steels in which carbon percentage is more than 0.8% are called hyper-eutectoid steel. High-Speed Steel is a high carbon tool steel, containing a large dose of tungsten. A typical HSS composition is: 18% tungsten, 4% Chromium, 1% Vanadium, 0.7% carbon and the rest, Iron.

What is Eutectoid point in phase diagrams?

The location on a phase diagram indicating the eutectoid composition and eutectoid temperature of an alloy. The eutectoid point also indicates the location at which three solid phases co-exist. In the iron-carbon phase diagram, this point indicates a temperature of 1333 F and a carbon content of 0.8%.

Is cast iron Hypereutectoid?

Cast iron: more than 2% Steel: less than 2% Hypereutectoid steels: greater than 0.8% and less than 2%

What is eutectoid point in phase diagrams?

What is the microstructure of martensite?

The microstructure of martensite contains many needle-shaped features, which cause martensite to be very brittle. While the main disadvantage of martensite is that it’s very brittle, martensite is desirable because it’s also very hard.