Metals are classified as ferrous and non-ferrous forms. The list of ferrous metals is counted from Iron (Fe), Chromium (Cr), Manganese (Mn) and all their alloys. Remaining all metal groups come under the section of non-ferrous category. The vast number non-ferrous metals differentiated into four types and they are Heavy metals, Light metals, Noble or precious metals, rare metals.
|High melting metals||Heavy metals||Light metals||Scattered metals||Rare earth metals||Radioactive metals||Small metals|
Every metal have definite crystal lattice which make it to be as solid crystalline substance. Based on the above property structure formation, shape and its physical properties are derived. Due to various temperature effect and condition of formation same metal can have different crystal forms which we mean of allotropic transformations.
Body centred cubic structure
|α-Iron, Chromium, Vanadium, Molybdenum, Tungsten, Sodium, Potassium|
Face centred cubic crystal
|γ –Iron, Nickel, Cobalt, Copper, Aluminium, Gold, Calcium|
|Zinc, Magnesium, Cadmium, Titanium|
Characteristics of metals:
Out of 109 elements there are 80% of metals in periodic table. They possess distinct characteristics as;
- At room temperature all metal are in solid state but not mercury.
- They shine when polished or cutted with tools.
- They can be made into foils by the property of malleability.
- They can be formed into wire due to ductility.
- Have free valency electrons which can be removed to ionize.
- Most of them are hard but alkali metals are soft in nature.
- Obviously they are supports of heat and electricity.
- Physical properties like thermal conductivity, electrical conductivity exhibit in high ranges in metals than other substances.
- Density of a metal is high but for lithium, sodium and potassium they have light density.
- They attain positive charge if they lose electron because of it low ionization potential.
- Melting point temperature are high may be they exceed 1000oC.
Metals Physical properties in simple way:
- Specific heat: It is said that when 1 gram of substance is subjected to heat source so that it take some specific quantity of heat energy to increase its existing temperature by 1 degree centigrade.
- Specific gravity: It is a value obtained as the ratio of weights of a metal and water is taken when both volumes are equal.
- Weldability: It determines a metal joining together when high temperature and pressure are applied.
- Elasticity: It accounts to the metals regaining to its original size after applying and removing a load.
- Plasticity: It is opposite to elasticity property of metals.
- Stiffness: It is the resisting capacity of metal when it takes a load.
- Porosity: It determines pore volume in metal.
- Fusibility: When heat is applied it determines the capability of metal melting scheme.
- Fluidity: During manufacturing process liquid metal is poured into moulds with the fluidity of metal.
- Ductility: Silver has high ductility has it can be made into wires.
- Malleability: Gold have high malleability has it can be made into as thin sheets as possible.
- Hardness: It is simple diamond is hardest so the metals have it.
- Toughness: Metal which can withstand to the bending forces due to its toughness.
- Brittleness: Opposite to toughness.
- Machinability: Property which determines the fabrication application.
- Tensile strength: Holding the tearing point during application of force.
- Refractoriness: Withstanding capacity to higher temperatures without melting.
- Shear strength: capability to maintain its shape without distorting.
- Impact resistance: Withstanding capability to sudden shocks.
- Fatigue resistance: Handling of repeated stresses.
- Creep resistance: Deformation property of metals
- Resilience: Bending and compressing load can’t change a metals original form after they are released.
- Magnetic property: If they attracted by magnet and have north and south poles.
Methods and techniques of metals production:
Rhenium: It is extracted by solvent extraction from molybdenite dust during the ore roasting process. Solvents like tributyl phosphate and kerosene are best suitable for solvent extraction/ leaching operation using mixer settler equipments.Other popular methods like vigorous ion exchange, batch precipitation, dual adsorption and supportive dense membrane are used based on the concentration of rhenium present in the ore mixture. It is used to make metal alloys