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Metallurgical Engineering Steel Making In Metallurgy Difficulty: Medium

Stainless steels are The reductant used in the extraction of magnesium from calcinated dolomite via Pidgeon's process is Match the cast irons in Group 1 with the distinguishing microstructural features in Group 2 . Group 1 Group 2 P. Grey cast iron 1. Temper graphite Q. Ductile cast iron 2. Pearlite R. Malleable cast iron 3. Graphite flakes S. White cast iron 4. Massive cementite 5. Nodular graphite Match the forming methods in Group 1 with the defects in Group 2 . Group 1 Group 2 P. Extrusion 1. Flash cracking Q. Closed die forging 2. Fir-tree cracking R. Rolling 3. Alligatoring 4. Earing A simplified energy band-diagram of an intrinsic semiconductor at thermal equilibrium (300 K) is shown. In the accompanying table, which one of the four cloumns correctly represents the listed parameters? Assume same effective mass for electrons and holes. Parameter Energy-difference Column 1 Column 2 Column 3 Column 4 Band-gap ΔE 2 ΔE 1 ΔE 2 ΔE 1 Electron affinity $$\frac{{\Delta {E_1}}}{2}$$ ΔE 2 - ΔE 1 $$\frac{{\Delta {E_2}}}{2}$$ ΔE 2 - $$\left( {\frac{{\Delta {E_1}}}{2}} \right)$$ Work function ΔE 1 + ΔE 2 ΔE 2 - $$\left( {\frac{{\Delta {E_1}}}{2}} \right)$$ ΔE 1 - $$\frac{{\Delta {E_2}}}{2}$$ ΔE 2 + $$\left( {\frac{{\Delta {E_1}}}{2}} \right)$$