Q6/ It is required to enhance the wear resistance of steel part by Nitriding process. To perform such task, the nitrogen surface concentration must be increased to 0.5 wt% while the initial value was 0.002 wt%. The nitrogen gas with constant temperature is provided from external source. To optimize the diffusion process; the subsurface layer of 0.4 mm depth, must has nitrogen content of 0.1 wt%. Find out the required process temperature to accomplish this treatment at 1.6 hour. The values of activation energy and preexponential for the nitrogen in iron at this temperature are 76,150 J/mol and 3 x 107 m2/s, respectively.

Q6/ It is required to enhance the wear resistance of steel part by Nitriding process. To perform such task, the nitrogen surface concentration must be increased to 0.5 wt% while the initial value was 0.002 wt%. The nitrogen gas with constant temperature is provided from external source. To optimize the diffusion process; the subsurface layer of 0.4 mm depth, must has nitrogen content of 0.1 wt%. Find out the required process temperature to accomplish this treatment at 1.6 hour. The values of activation energy and preexponential for the nitrogen in iron at this temperature are 76,150 J/mol and 3 x 107 m2/s, respectively.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.46P

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