List of top Metallurgy Questions asked in GATE MT

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: \(1455^{\circ}\text{C}\))
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 ______ %.