Engineering, 20.07.2019 00:10 jolleyrancher78
Gears are to be subjected to the process of gas carburizing in which ch4 disassociates at the metal surface and the c diffuses into the steel forming a thin carbon-rich layer which can then be hardened by appropriate heat treatment. the gears are of steel, originally containing 0.17% c. the diffusion coefficient (do) for carbon in austenite is 0.21 sq cm/sed and the activation energy is33.8 kcal/mole. the process is maintained at a temperature of 975°c.. if the surface of the metal is maintained at a carbon content of 1.1 per cent, what will be the time required to increase the carbon content 0.5 mm below the surface to 0.5 per cent? what will be the carbon content 1.5 mm below the surface at that time?
Answers: 1
Engineering, 03.07.2019 14:10
If the thermal strain developed in polyimide film during deposition is given as 0.0044. assume room temperature is kept at 17.3 c, and thermal coefficient of expansion for the film and the substrate are 54 x 10^-6c^-1 and 3.3 x 10^-6c^-1respectively. calculate the deposition temperature.
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Engineering, 04.07.2019 18:10
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Answers: 1
Engineering, 04.07.2019 18:10
Afluid flows with a velocity field given by v=(x/t)i.. determine the local and convective accelerations when x=3 and t=1.
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Engineering, 04.07.2019 18:10
An ideal otto cycle with air as the working fluid has a compression ratio of 8. the minimum and maximum temperatures in the cycle are 300 k and 1340 k. use constant specific heats at room temperature to determine (a) the amount of heat transferred to the air during the heat- addition kj/kg, (b) the thermal efficiency, and (c) the thermal efficiency of a carnot cycle ope limits. process, in rating between the same temperature
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Gears are to be subjected to the process of gas carburizing in which ch4 disassociates at the metal...
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