6.4. Annealing is a process by which steel is reheated and then cooled to make it less brittle. Consider the reheat stage for a 100-mm-thick steel plate (p = 7830 kg/m³, c = 550 J/kg • K, k = 48 W/m⚫ K), which is initially at a uniform temperature of T₁ = 200°C and is to be heated to a minimum temperature of 550°C. Heating is effected in a gas-fired furnace, where products of combustion at T∞ = 800°C maintain a convection coefficient of h = 250 W/m² ⚫ K on both surfaces of the plate. How long should the plate be left in the furnace?

6.4. Annealing is a process by which steel is reheated and then cooled to make it less brittle. Consider the reheat stage for a 100-mm-thick steel plate (p = 7830 kg/m³, c = 550 J/kg • K, k = 48 W/m⚫ K), which is initially at a uniform temperature of T₁ = 200°C and is to be heated to a minimum temperature of 550°C. Heating is effected in a gas-fired furnace, where products of combustion at T∞ = 800°C maintain a convection coefficient of h = 250 W/m² ⚫ K on both surfaces of the plate. How long should the plate be left in the furnace?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.39P: The tip of a soldering iron consists of a 0.6-cm- diameter copper rod, 7.6 cm long. If the tip must...

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