List of top Metallurgy Questions

In a rolling operation, a 200 mm wide strip of 23 mm thickness needs to be reduced to 20 mm in a single pass. The roll diameter is 200 mm. Four lubricants P, Q, R, and S with coefficient of friction 0.05, 0.1, 0.2, and 0.25, respectively, are available for use at the roll-strip interface. Assume that the strip width remains constant throughout the process.

Which ONE or MORE among the following lubricants will enable the rolling process to achieve the desired final thickness of the strip in a single pass?
Iron powder is compacted at room temperature to 75% of its theoretical density. The as-pressed iron compact is sintered in inert-gas atmosphere at \(1200^{\circ}\text{C}\) to 90% of its theoretical density. Assuming isotropic shrinkage, the linear shrinkage (in percent) undergone by the iron compact during sintering (rounded off to one decimal place) is ______ %.
An alloy having composition W-20 wt.% Ni is prepared by mixing elemental powders. The resulting powder mixture is liquid phase sintered at \(1550^{\circ}\text{C}\) for 1 hour. The liquid phase sintered microstructure consists of interconnected, spherical tungsten grains dispersed in nickel. The tungsten grain size is 70 \(\mu\text{m}\) and the W-W interparticle neck diameter is 35 \(\mu\text{m}\). If W-Ni interfacial energy is 0.30 J/m\(^2\), the W-W interfacial energy (in J/m\(^2\)), rounded off to two decimal places is ______.
(Given: melting point of W: \(3410^{\circ}\text{C}\) and melting point of Ni: \(1455^{\circ}\text{C}\))
If the density function of X equals f(x) \(=\) \(\begin{cases} ce^{-2x}, & 0 \lt x \lt \infty \\ 0, & x \lt 0 \end{cases}\), then P(X \(\gt \) 2) is
The Newton-Raphson method is used to find the root of the equation f(x) \(\equiv\) x\(^2\) \(-\) x \(-\) 1 \(=\) 0. If the initial guess for the root is 1, then the estimate of the root after two iteration is
Suppose that the average number of accidents occurring weekly on a particular stretch of a highway equals 3. The probability that there is at least two accidents in a week is
The solution of the differential equation \(\frac{d^3y}{dx^3} - 5\frac{d^2y}{dx^2} + 8\frac{dy}{dx} - 4y = 0\) is
If f(x, y) \(=\) x\(^3\)y \(+\) xy\(^3\) \(+\) e\(^{xy^2}\), then f\(_y\)(1, 1) is
If F(s) denotes the Laplace transform of some function f(t), then the Laplace transform of e\(^{-at}\)f(t), where a is a real constant, is
Under which one of the following conditions does the system of equations \(\begin{pmatrix} 1 & 2 & 4 \\ 2 & 1 & 2 \\ 1 & 2 & k-4 \end{pmatrix} \begin{pmatrix} x \\ y \\ z \end{pmatrix} = \begin{pmatrix} 6 \\ 4 \\ k \end{pmatrix}\) have a unique solution?
Let S be the surface of the cube bounded by x \(=\) 0, x \(=\) 1, y \(=\) 0, y \(=\) 1, z \(=\) 0, z \(=\) 1. The value of the surface integral \(\iint_S \vec{F} \cdot d\vec{s}\) of a vector field \(\vec{F} = 4xz \hat{i} - y^2 \hat{j} + yz \hat{k}\) over the entire surface S of the cube, is _____
If y\(_1\) and y\(_2\) be two solutions of the differential equation \(\frac{d^2y}{dx^2} + 2y = f(x)\), then y\(_1\) + y\(_2\) is also solution of
The modulus of resilience is equal to:
Let A be a 3 \(\times\) 3 matrix such that the characteristic polynomial of A is f(x) \(=\) x\(^3\) \(-\) 4x\(^2\) \(-\) 11x \(+\) 30. If one of the eigenvalues of A is \(-\)3, then sum of the other two eigenvalues is
Alloy A has a narrow freezing range as compared to Alloy B. Considering both alloys solidify under identical conditions, which statement is correct regarding feeding?
The fracture surface in ductile fracture generally shows
Heat transfer in vacuum occurs by:
The atomic packing factor (APF) of FCC structure is approximately
The formation of a passive layer decreases corrosion rate because it
The main purpose of vulcanization of rubber is to
The PCE (Pyrometric Cone Equivalent) value indicates:
Reverberatory furnaces are mainly used for:
The alumina obtained from Bayer process is converted to aluminium metal by:
The atomic packing factor (APF) for BCC structure is approximately
In ferromagnetic materials, magnetic domains: