Three metallic samples are examined at 25 °C.
• Sample A: pure iron
• Sample B: low-carbon steel containing 0.10 mass % carbon
• Sample C: an Fe–Ni alloy containing 10.0 mass % nickel
All three samples have similar grain size and have not been mechanically cold-worked.
(a) Describe, at the particulate level, the essential features of metallic bonding in pure iron.
(b) Rank the three samples in order of expected hardness from hardest to softest. Justify your ranking in terms of lattice structure.
(c) For each sample, predict its relative malleability/ductility compared with the other two and explain the reasoning behind your predictions.
(d) Identify which sample is expected to have the greatest electrical conductivity. Provide an explanation based on how the alloying element(s) affect electron movement.