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Rapid quenching of eutectoid steel ___________ transforms the austenite into martensite.

Rapid quenching of eutectoid steel ___________ transforms the austenite into martensite. Correct Answer Above 723oC

An isothermal transformation of eutectoid steel between 723oC and 550oC gives a pearlitic microstructure. Rapid quenching above 723oC transforms the austenitic condition into martensitic condition.

Related Questions

A binary phase diagram of components P and Q displays an eutectoid reaction with terminal solid solutions a on the P rich side and β on the Q rich side. At the eutectoid temperature, the solubilities of Q in a and β are 5 and 90 wt% respectively. The densities of α and β phases are 9.5 and 2.49 gm/cm3 respectively.
At the eutectoid point, the alloy has α and β in the weight ratio 1 : 1. The eutectoid point occurs at composition . . . . . . . . wt % Q.
A steel contains 38.5 mass % pro-eutectoid ferrite and 61.3 mass % austenite at eutectoid temperature (723°C). The carbon content of steel, in mass %, is
Arrange the following in terms of increasing severity of quench.
P. Oil quenching
Q. Water quenching
R. Water quenching with agitation
S. Brine quenching
Statement (I): Salts like sodium chloride, sodium hydroxide when added to water to use as quenching media, cooling rate of quenching media will be increased. Statement (II): When salts are added to water, during quenching, distortion and crack appearance in the quenched steel components reduces.
In Eutectoid reaction a solid phase transforms into two other solid phases upon cooling. Which one of the following is correct in the case of Eutectoid reaction occurring in Iron-Carbon phase diagram?
Consider the following statements: 1. The quenching of steel results in an increase in wear resistance, strength and hardness. 2. By the process of case hardening, hard wearing resistant surface is produced on mild steel. This is an effective method for low carbon steels because they cannot be hardened by the process of quenching. 3. When a metal is mixed with small atoms of non-metallic element in such a manner that invading atoms occupy interstitial positions in the metal lattice, an interstitial alloy results. What of the above statements are correct?
Match the heat treatment for an eutectoid steel shown in the TTT diagram below (as P, Q, R and S) with the resulting microstructure listed below:
1. Fine pearlite
2. martensite
3. Bainite
4. Coarse pearlite
Physical Metallurgy mcq question image
Quenching of austenite steel for martempering is done using __________
Tempered martensite has better ductility than martensite.
Which of the following processes permits the transformation of austenite to martensite, throughout the crosssection of a component without cracking or distortion?