List of top Questions asked in GATE Metallurgical Engineering

Radiative heat flux $\dot{q$ at a hot surface at a temperature $T_s$ can be expressed as} \[ \dot{q} = A \, f(T_s, T_\infty) \, (T_s - T_\infty) \] where $A$ is a constant and $T_\infty$ is the temperature of the surroundings (all temperatures in K). The function $f(T_s, T_\infty)$ is given by ____.

Match the phenomena in Column I with the typical observations in Column II. Column I:
P. Dynamic strain aging
Q. Recrystallization
R. Bauschinger effect
S. Superplasticity
Column II:
1. Grain boundary sliding
2. Decrease in yield stress with a reversal of loading direction
3. Decrease in dislocation density
4. Serrations in stress–strain curve

Which one of the following matrices is orthogonal?

Match the casting defects in Column I with the characteristic features in Column II. Column I:
P. Misrun
Q. Expansion scab
R. Pin holes
S. Hot tearing
Column II:
1. Penetration of liquid metal behind surface layer of sand moulds
2. Metal solidifies prematurely in the mould and some sections of the casting are not filled
3. Cracking because of restraint to contraction in certain areas during solidification and cooling
4. Evolution of gases during solidification resulting in porosity

For an application where the Reynolds number is to be kept constant, a liquid with density of 1 g per cubic cm and viscosity of 0.01 Poise results in a characteristic speed of 1 cm per second. If this liquid is replaced by another with density of 1.25 g per cubic cm and viscosity of 0.015 Poise, the characteristic velocity will be ........... cm per second (rounded off to one decimal place). Assume the characteristic length of the flow to be the same in both cases.

For two continuous functions M(x,y) and N(x,y), the relation M dx + N dy = 0 describes an exact differential equation if

Consider the phase diagram of a one component system. Va, Vb and Vliquid are the molar volumes of alpha, beta and liquid phases respectively. Which one of the following statements is true?
\begin{center} \includegraphics[width=0.7\textwidth]{05.jpeg} \end{center} Given: The change in molar enthalpies, DeltaH alpha to beta and DeltaH beta to liquid, are positive.

Match the steel plant related processes in Column I with the associated information in Column II. Column I: P. Corex
Q. Electric Arc Furnace
R. Midrex
S. Continuous Casting
Column II: 1. Melter-gasifier
2. Natural gas reformer
3. Electromagnetic stirrer
4. Hot heel

Standard Gibbs free energies of formation of oxides per mole of O2 at 1000 K are given below. SiO2: -728 kJ, TiO2: -737 kJ, VO: -712 kJ, MnO: -624 kJ. Regarding thermodynamic feasibility of oxide reduction, which of the following statements is or are CORRECT under standard conditions at 1000 K?

Consider a fully developed, steady, one-dimensional, laminar flow of a Newtonian liquid through a pipe. The maximum velocity in the pipe is proportional to which of the following quantities? Given: Delta P is the difference between the outlet and inlet pressure, mu is the dynamic viscosity of the liquid, and R and L are radius and length of the pipe, respectively.

The hydrostatic stress for the stress tensor provided below is .............. MPa (in integer). \[ \begin{bmatrix} 150 & 0 & 0
0 & -100 & 100
0 & 100 & 250 \end{bmatrix} \, \text{MPa} \]

Which of the following conditions is/are favorable for producing low-silicon hot metal in blast furnace ironmaking?

Which of the following statements is or are CORRECT with respect to the initial stage of GP zone formation in a precipitation hardenable Al - 4.5 wt.\% Cu alloy?

Which of the following techniques can be used to detect an internal defect in a metal casting?

In the Fe–C system, the invariant reaction \( \text{Liquid} + \delta \rightleftharpoons \gamma \) occurs at \(1493^{\circ}\text{C}\). This reaction is called _____.

Match the following elements in Column I with their respective ores in Column II. \begin{center} \begin{tabular}{|l|l|} \hline Column I & Column II
\hline P. Al & 1. Rutile
\hline Q. Fe & 2. Hematite
\hline R. Ti & 3. Chalcopyrite
\hline S. Cu & 4. Bauxite
\hline \end{tabular} \end{center}

Which of the following functions is/are expandable using Maclaurin series?

With reference to edge and screw dislocations, which of the following statements is/are CORRECT?

Which one of the following slag components is responsible for the oxidizing power of steelmaking slags?

Two randomly oriented polycrystalline copper samples with average grain sizes of 10 \(\mu\)m (Sample A) and 100 \(\mu\)m (Sample B) were tested at room temperature. Let \(E_A, E_B\) be the Young's moduli and \(YS_A, YS_B\) the yield strengths of A and B. Which statement is \emph{correct?}

In metal casting, which sprue:runner:gate \emph{area ratio represents a non-pressurized gating system?}

In optical microscopy, which one of the following combinations of wavelength (\(\lambda\)) and numerical aperture (NA) provides the best spatial resolution?

The coordination number for an octahedral site in pure copper is ____.

Consider the following gas-phase reaction: \[ 2SO_2 + O_2 \;\rightleftharpoons\; 2SO_3 \] If the enthalpy of reaction is negative, which condition promotes a higher equilibrium concentration of \(SO_3\)?

Match each crystal defect in Column I with the corresponding type in Column II. Column I:
P. Edge dislocation
Q. Stacking fault
R. Frenkel defect
S. Porosity
Column II:
1. Zero-dimensional defect
2. One-dimensional defect
3. Two-dimensional defect
4. Three-dimensional defect