How do we get Martensitic start and finish temperature?
How do we get Martensitic start and finish temperature?
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since homogeneous system is that system which consists of single phase so can we say that at room temperature all the pure metal comes under homogeneous system?
since homogeneous system is that system which consists of single phase so can we say that at room temperature all the pure metal comes under homogeneous system?
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Hello, I would like to know your opinion on the method by which this steel was made. What distinguishing features of forging from rolled products are visible on the microstructure? (30 X magnification)
Hello, I would like to know your opinion on the method by which this steel was made. What distinguishing features of forging from rolled products are visible on the microstructure?
(30 X magnification)
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The equilibrium microstructure of an alloy A-B consists of two phases α and β in the molar proportion 2:1. If the overall composition of the alloy is 70 mol% B and the composition of β is 90 mol% B, the ...Read more
The equilibrium microstructure of an alloy A-B consists of two phases α and β in the molar proportion 2:1. If the overall composition of the alloy is 70 mol% B and the composition of β is 90 mol% B, the composition of α is _______(in mol% B) (round off to the nearest integer).
Read lessGiven the stress tensor, the maximum shear stress is MPa (round off to the nearest integer).
Given the stress tensor, the maximum shear stress is MPa (round off to the nearest integer).
Air at 300 K is passed at a mass flow rate of 1.5 kgs1 through a metallic tube of inner diameter 0.08 m. Inner wall temperature of the tube is maintained at 700 K. Temperature of the air leaving the ...Read more
Air at 300 K is passed at a mass flow rate of 1.5 kgs1 through a metallic tube of inner diameter 0.08 m. Inner wall temperature of the tube is maintained at 700 K. Temperature of the air leaving the tube is 600 K. Assuming that heat transfer occurs entirely by steady state convection, length of the tube is ______ m (round off to 2 decimal places).
Given: the coefficient of convective heat transfer from tube wall to air is 500 Wm2 K1. Assume specific heat capacity of air to be constant and equal to 1080 Jkg1K1 and π = 3.14
Read lessA cylindrical specimen of an Al alloy with diameter of 30 mm is cold extruded to a diameter of 20 mm. If the flow behavior of the alloy is expressed by the equation, 𝜎 = 350 𝜖0.3 MPa, the ideal ...Read more
A cylindrical specimen of an Al alloy with diameter of 30 mm is cold extruded to a diameter of 20 mm. If the flow behavior of the alloy is expressed by the equation, 𝜎 = 350 𝜖0.3 MPa, the ideal plastic work of deformation per unit volume is ____ × 106 J (answer rounded off to the nearest integer).
Read lessSteel plates are welded autogenously using Gas Tungsten Arc welding with an arc heat transfer efficiency of 0.65. The first weld is made using a welding current of 200 A at an arc voltage of 18 V with a welding ...Read more
Steel plates are welded autogenously using Gas Tungsten Arc welding with an arc heat transfer efficiency of 0.65. The first weld is made using a welding current of 200 A at an arc voltage of 18 V with a welding speed of 0.002 ms–1.
The second weld is made at a welding speed of 0.0022 ms–1 with the same arc voltage. If both the welds have identical heat input, the welding current of the second weld is _____ A (round off to the nearest integer).
Read lessA sieve made of steel wire of diameter 53 µm has an aperture size of 74 µm. Its mesh number is ______ . (round off to the nearest integer).
A sieve made of steel wire of diameter 53 µm has an aperture size of 74 µm. Its mesh number is ______ . (round off to the nearest integer).
Read lessAssuming that Dulong-Petit law is valid for a monoatomic solid, the ratio of heat Cp/Cv capacities at 500 K is _____. (round off to 3 decimals). Given: molar volume = 7×106 m3 mol-1, isothermal compressibility = 8×1012 Pa1, isobaric expansivity = 6×105K1 ...Read more
Assuming that Dulong-Petit law is valid for a monoatomic solid, the ratio of heat
Cp/Cv capacities at 500 K is _____. (round off to 3 decimals).
Given: molar volume = 7×106 m3 mol-1, isothermal compressibility = 8×1012 Pa1, isobaric expansivity = 6×105K1 andR = 8.314 JK-1mol-1.
Read lessThe concentration 𝐶 of a solute (in units of atomsmm3) in a solid along 𝑥 direction (for 𝑥 > 0) follows the expression 𝐶 = 𝑎1𝑥2 + 𝑎2𝑥 where 𝑥 is in mm, 𝑎1 and 𝑎2 are in units of atomsmm5 ...Read more
The concentration 𝐶 of a solute (in units of atomsmm3) in a solid along 𝑥 direction (for 𝑥 > 0) follows the expression 𝐶 = 𝑎1𝑥2 + 𝑎2𝑥 where 𝑥 is in mm, 𝑎1 and 𝑎2 are in units of atomsmm5 and atoms mm4, respectively. Assuming 𝑎1= 𝑎2= 1, the magnitude of flux at 𝑥 = 2 mm is _____ × 10–3 atomsmm2 s1 (answer rounded off to the nearest integer). Given: diffusion coefficient of the solute in the solid is 3 × 10–3 mm2⋅s1.
Read lessDuring solidification of a pure metal, the radius of critical nucleus at an undercooling of 10 K is ______ × 10–9 m (answer rounded off to 1 decimal place). Given: solid/liquid interface energy = 0.177 Jm-2, melting point of the metal ...Read more
During solidification of a pure metal, the radius of critical nucleus at an undercooling of 10 K is ______ × 10–9 m (answer rounded off to 1 decimal place).
Given: solid/liquid interface energy = 0.177 Jm-2, melting point of the metal = 1356 K and latent heat of fusion = 1.88 × 109 Jm-3
Read lessA rectangular block made of Material I and Material II of identical cross sections (as shown in the figure) has a temperature (T) of 435 K and 400 K at the bottom and top surfaces, respectively. Assuming purely steady state ...Read more
A rectangular block made of Material I and Material II of identical cross sections (as shown in the figure) has a temperature (T) of 435 K and 400 K at the bottom and top surfaces, respectively. Assuming purely steady state conductive heat transfer, the temperature at the interface is _ K (round off to nearest integer).
(Given: The two parts of the block made of Material I and Material II have equal thickness of 25 mm each. The thermal conductivities of Material I and Material II are 50 Wm1K1 and 200 WM1K1, respectively.)
The partial molar enthalpy of Au in Ag-Au melt containing 25 mol% Au at 1400 K is 8300 Jmol1. Assuming regular solution behavior, the activity of Au in the melt is (round off to 3 decimal places). Given: R ...Read more
The partial molar enthalpy of Au in Ag-Au melt containing 25 mol% Au at 1400 K is 8300 Jmol1. Assuming regular solution behavior, the activity of Au in the melt is (round off to 3 decimal places). Given: R = 8.314 JK1mol1
Read lessHigh cycle fatigue data for an alloy at various alternating stresses, 𝜎a (see figure) is given below. A specimen of this alloy is subjected to multiple stress cycles sequentially in the following order: (i) first 5000 cycles at σa = ...Read more
High cycle fatigue data for an alloy at various alternating stresses, 𝜎a (see figure) is given below.
A specimen of this alloy is subjected to multiple stress cycles sequentially in the following order: (i) first 5000 cycles at σa = 400 MPa followed by (ii) 25000 cycles at σa = 300 MPa and finally (iii) at σa = 500 MPa. Assuming that Miner’s law is obeyed, the number of cycles to failure at the final applied stress of
500 MPa is .
Molten steel at 1873 K weighing 100 metric tons is desulfurized using 1250 kg of synthetic slag by equilibration. If the sulfur content in the steel is reduced from 0.015 mass% to 0.0025 mass%, the desulfurizing index is _______. ...Read more
Molten steel at 1873 K weighing 100 metric tons is desulfurized using 1250 kg of synthetic slag by equilibration. If the sulfur content in the steel is reduced from 0.015 mass% to 0.0025 mass%, the desulfurizing index is _______. (round off to the nearest integer).
Read lessConsider a tilt boundary of misorientation of 2o in an aluminium grain. The lattice parameter of aluminium is 0.143 nm. The spacing between the dislocations that form the tilt boundary is ______ nm (round off to 2 decimal places).
Consider a tilt boundary of misorientation of 2o in an aluminium grain. The lattice parameter of aluminium is 0.143 nm. The spacing between the dislocations that form the tilt boundary is ______ nm (round off to 2 decimal places).
Read lessThe emf of the cell Au-Pb(liquid) PbCl2-KCl(liquid) Cl2(gas, 0.5 atm), C(graphite) is 1.2327 V at 873 K. Activity of Pb in the Au-Pb alloy is 0.72 and the activity of PbCl2 in the electrolyte is 0.18. The standard Gibbs energy of formation ...Read more
The emf of the cell
Au-Pb(liquid) PbCl2-KCl(liquid) Cl2(gas, 0.5 atm), C(graphite)
is 1.2327 V at 873 K. Activity of Pb in the Au-Pb alloy is 0.72 and the activity of PbCl2 in the electrolyte is 0.18. The standard Gibbs energy of formation of PbCl2(liquid) at 873 K is kJmol1 (round off to 1 decimal place). Given: R = 8.314 JK1mol1 and F = 96500 Cmol1.
Read lessWhat is the equilibriumpC0 / pC02 ratio for the given reaction at 1873 K? (round off to 2 decimal places) Mo(s) + O2(g) MoO2(s) Given: Δf𝐺1873∘ = 262300 J; 𝑎MoO 2 (s) = 0.5 and Δr𝐺 1873∘ = 120860 J for ...Read more
What is the equilibriumpC0 / pC02 ratio for the given reaction at 1873 K? (round off to 2 decimal places)
Mo(s) + O2(g) MoO2(s)
Given: Δf𝐺1873∘ = 262300 J; 𝑎MoO 2 (s) = 0.5 and Δr𝐺 1873∘ = 120860 J for the
reaction CO(g) + 0.5O2(g) CO2(g); R = 8.314 JK1mol1.
Read lessA spherical gas bubble of radius 0.01 mm is entrapped in molten steel held at 1773 K. If the pressure outside the bubble is 1.5 bar, the pressure inside the bubble is _____ bar (round off to 1 decimal place). Given: ...Read more
A spherical gas bubble of radius 0.01 mm is entrapped in molten steel held at 1773 K. If the pressure outside the bubble is 1.5 bar, the pressure inside the bubble is _____ bar (round off to 1 decimal place). Given: 1 bar = 105 Pa and the surface tension of the steel at 1773 K is 1.4 N⋅ m–1.
Read lessFrom high temperature tensile testing, the flow stress (measured at the same value of strain) of an alloy was found to be 50 MPa at a strain rate of 0.1 s–1 and 70 MPa at a strain rate of 10 ...Read more
From high temperature tensile testing, the flow stress (measured at the same value of strain) of an alloy was found to be 50 MPa at a strain rate of 0.1 s–1 and 70 MPa at a strain rate of 10 s–1. The strain rate sensitivity parameter is (round off to 3 decimal places).
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