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MSE 258:Physical Metallurgy of Non-Ferrous Metals
Dr. Emmanuel Kwesi Arthur
Department of Materials Engineering,
Kwame Nkrumah University of Science and Technology, Kumasi
2019
Lecture Two
‘Ferrous metal’ or ‘Ferrous alloy’
What is a ‘ferrous metal’ or ‘ferrous alloy’? It is simply a metal or alloy that contains Iron (the element ferrous) as the base (starting) metal.
Approximately 90% of the world’s production of metals/alloys are ferrous because of their good strength, toughness, ductility and relatively low cost.
26th element
Iron or Ferrous
55.85 Atomic Mass
Nonferrous metals offer a wide variety of mechanical
properties and material characteristics.
Nonferrous metals are specified for structural
applications requiring reduced weight, higher strength,
nonmagnetic properties, higher melting points, or
resistance to chemical and atmospheric corrosion.
They are also specified for electrical and electronic
applications.
Nonferrous metals
Quiz 1
1) What is the main difference between ferrous and non ferrous metals?
2) What is pewter used for? 3) Give two examples of an alloy4) Give two examples of a non-ferrous metal.5) Give two examples of a ferrous metal.
World consumption
Aluminium, titanium and magnesium alloys are increasingly used in recent years due to its attractive properties.
The reserves for these alloys are adequate for demands in centuries to come but will be controlled by future cost.
World production figure for various metals and plastics.
Total energy consumption for the production of nonferrous metals
Total energy consumption
Total energy consumption in megawatt hours for each stage of production (1993).
Fact- About 6.2kWH of electricity is required to produce one pound of aluminium from alumina
1. General (heavy) non-ferrous metalsa) with medium melting temperature: Cu, Ni, Co, Mnb) with low melting temperature: Zn, Cd, Hg, Pb, Bi, Sn, Sb, Ga, In, Tl
2. Light metalsa) with medium melting temperature: Al, Mg, Be, Ca, Sr, Bab) with low melting temperature (alkali metals): Li, Na, K, Rb, Cs
Note: some authors consider even Ti-4.5 g/cm3
3. Noble (precious) metalsa) with medium melting temperature: Ag, Aub) with high melting temperature: Ru, Rh, Pd, Os, Ir, Pt
Non-ferrous metals and their alloys
Cu Ni Co Mn Zn Cd Hg Pb Bi
Tm oC 1085 1455 1495 1246 419.5 321.1 -38.83 327.5 271.4
Sn Sb Ga In Tl Al Mg Be Ca
Tm oC 231.9 630.6 29.76 156.6 304 660 650 1287 842
Sr Ba Li Na K Rb Cs Ag Au
Tm oC
4. High melting temperature metalsa) with BCC lattice: W, Ta, Nb, Mo, V, Crb) with HCP lattice: Ti, Zr, Hf, Tc, Re
5. Rare earth metalsa) trace metals: Sc, Y, Lab) Lanthanides (at. no. 58-71): Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er,
Tm, etc.6. Radioactive metals, transuranides and transactinides
a) naturally occurring radioactive metals: Po, Fr, Ra, U, Th, Pa, Acb) transuranides and actinides (at. no. 93-103): Np, Pu, Am, Cm, Bk, Cf, Es,
Fm, Md, No, Lrc) transactinides and superactinides (at. no. 104-168): Rf, Db, Sg, Bh, Hs,
Mt, Ds, ....?
Non-ferrous metals and their alloys
Classification of non-ferrous materials
a) Density based:
– light metals and alloys ρ < 5000 kg/m3 (Mg, Al, Ti)
– medium metals and alloys ρ = 5000...10000 kg/m3 (Sn, Zn, Sb, Cr, Ni, Mn, Cu)
– heavy metals and alloys ρ >10000 kg/m3 (Pb, Ag, Au, Ta, W, Mo)
b) Melting temperature based:
– low melting point Tm < TmPb = 327 °C (Sn, Pb, Bi)
– medium melting point = 327…1539 °C (Al, Mg, Mn, Cu, Ni, Co, Ag, Au)
– refractory Tm > TmFe = 1539 °C
11
Element Ti Cr V Nb Mo Ta W
Tm, °C 1660 1875 1900 2415 2610 2996 3410
Aluminum and Aluminum Alloys
Aluminum is an extremely useful engineering material as:o They are light weight and strong; Al has a density
of 2700 kg/m3, which is about 1/3 that of steel. o Their strength to weight ratio is excellent.o Al is non-toxic.o Al is one of the best metal electrical conductorso Al has good corrosion resistance due to its natural
oxide layer, which is thin and passive once formed.o Aluminum has ease of formability and of
machinablity and it is non magnetic
Quiz 2
1. Where do metals originate from? [1]2. Describe what a ferrous metal is? [1]3. Describe what a non ferrous metal is? [1]4. Describe what an alloy is? [1]5. How are alloys produced that have different
properties? [1]6. Explain the following properties:
Brittleness [1]Elasticity [1]Malleability [1]