For a steel alloy it has been determined that a carburizing heat treatment of 14 h duration at 763°C will raise the carbon concentration to 0.46 wt% at a point 2.2 mm from the surface. Estimate the time necessary to achieve the same concentration at a 5.3 mm position for an identical steel and at a carburizing temperature of 1000°C. Assume that D0 is 1.5 × 10–5 m2/s and Qd is 104 kJ/mol. (Hint – start with equation 5.6 from Callister text book)

Heat is added to a piston-cylinder device filled with 2 kg of air to raise its temperature 400 c from an initial temperature of t1 27 cand pressure of pi 1 mpa. the process is isobaric process. find a)-the final pressure p2 b)-the heat transfer to the air.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.