Problem 2
(i) One of the practical applications of diffusion is case hardening of steel. If you wish to increase the amount of carbon at a given depth below the surface, you should: (Please circle one)
a) Increase the temperature, increase the carbon content, and increase the time the steel part remains in the carburization furnace.
b) Increase the temperature, decrease the carbon content, and increase the time the steel part remains in the carburization furnace.
c) Decrease the temperature, decrease the carbon content, and increase the time the steel part remains in the carburization furnace.
d) Increase the temperature, increase the carbon content, and decrease the time the steel part remains in the carburization furnace.
(ii) An elastic limit is: (Please circle one)
a) The stress beyond which there is a permanent deformation.
b) Deformation that is recoverable when the load is removed.
c) A phenomenon that is the result of dislocation-dislocation interactions in metallic crystals.
d) The change in length of a specimen or component divided by the original length.
(iii) Within a cubic unit cell, choose a coordinate system, then sketch the (1 2 0) plane.