HW#2-515 pt,1D,semi-infinite,constant qProperties of Surface Target temperatures T=7x=0,1500K metallic materials are largely dependent on composition and for Heat Treatment Inner part Tx=0.004m,1200K phase and the phase changes with temperature. To achieve Initial temperature desirable properties by transforming a material phase, heat 7=Tx,=0=300K treatment is conducted.
Here, a thick slab of stainless steel is treated by supplying a constant heat flux q (W/m^2) on a surface. The initial temperature of the slab is T=300 K, and we want to treat its =8000 kg/m^3 With the resulting q, surface (reaching over 1500 K, while maintaining an inner c-500 J/kg-K Tx=0.004 m, r=100 s) temperature below 1200 K. The slab can be considered as a =16 W/m-K bFor T-Tx=0, =25 s-1500 K. q semi-infinite solid, and other heat transfer modes such as =4.010 m^2/s With the resulting convection or radiation are ignored. Tx=0.004 m, =25 s)? a) To reach the surface temperature of 1500 K at x=0 within t=100 sec, what should the minimum supplied heat flux (q W/m^2) be? With this q_s, find the temperature at 4 mm below the surface after 100 sec of heating, Tx=0.004 m t=100 sec b) If we want to reach the surface temperature of 1500 K at x=0 four times faster, i.e., within 25 sec (t=25 sec=t/4), what should the minimum supplied heat flux q" (W/m^2) be? Find the temperature at 4 mm below the surface after 25 sec of heating with q_s.
