Calculate the solidification time assuming no mould-casting resistance to heat flow for a slab of iron, 25 cm thick, poured with no superheat into, an iron mould a sand mould First guess t,(sand)/t, (iron) Approximate Thermal Data Mould and metal constants Specific heat, cal/(g.C) 0.27 Thermal conductivity, cal/(cm-Cs) 14.5 x 104 Material Density, g/cm Sand 1.5 Iron 0.16 7.3 0.07 Aluminium 0.20 2.7 0.53 0.09 9.0 0.94 per Magnesium 0.25 1.7 0.38 Liquid metal constants Specific heat, Melting point, cal/(g.C) 0.18 Heat of fusion, cal/g 65 Material C Iron 1540 Aluminium 0.26 660 95 1083 pper Magnesium 0.12 51 0.32 650 89