Bases of Existence of Properties in Materials

The properties of material changes from matter to matter. They vary depending on their chemical composition, electron configuration, atomic structure, impurities & imperfections, manufacturing process, and mechanical heat treatment process. The chemical composition of a material represents the elements which make up a material. This chemical composition decides whether the material is organic or inorganic, acid or alkaline etc. Electronic configuration represents the distribution of the electrons in an atom in its outer shell and subshells.

The electronic configuration determines the conductivity of a material, which decides whether the material is a good or bad conductor of electricity. Magnetic properties of materials also depend on the electron configuration of the atom.

The magnetic properties of a material are very much affected by the distribution of electrons in subshells and their spin direction. The atomic structure of a material indicates the manner in which the atoms are connected to each other such as crystalline or amorphous structures.

The table below shows the relationship between the properties and atomic structure of Metals, Ceramics, and Polymers.

Sl. No.Atomic StructureMetalsCeramicsPolymers (Plastic & rubber)
1CrystallinityCrystalline
  1. Crystalline
  2. Non-crystalline
  3. Crystalline and Non Crystalline Phase
Non crystalline
2BondingMetallicIonic and CovalentCovalent plus secondary
3Important properties
  • Excellent conductor of Heat
  • Excellent conductor of Electricity
  • Usually malleable and ductile
  • Opaque
  • Lustrous
  • Moderate to high melting point
  1. For Crystalline structure
    • Nonconductor of heat
    • Nonconductor of Electricity
    • Hard
    • High melting point
  2. For Non-crystalline
    • Nonconductor of heat
    • Nonconductor of Electricity
    • Hard
    • Brittle
    • No definite melting point
  3. For Crystalline and non crystalline phase
    • Very poor conductor of heat
    • Very poor conductor of electricity
    • Hard
    • Brittle
    • Low strength
    • High melting point
  • Very poor conductor of heat
  • Very poor conductor of Electricity
  • Low strength
  • Deformed plastically with small load
  • Low melting point

Moreover, in bulk material the properties of materials are also affected by the nature and distribution of impurities or imperfections, either chemical or architectural. The impurities or imperfections affect the strength of material very much. The conductivity of metals is affected very much by impurities in a metal. These impurities disturb the crystalline structure of metal and make it irregular. This irregularity in crystalline structure disturbs the movement of electrons through metal. Which results in reduction of conductivity of metal. A small level of impurities results in considerable reduction in conductivity of metal. The properties of material are also effected by manufacturing process as well as mechanical heat treatment processes i.e. Hardening, Annealing, age hardening, quenching, hot rolling, cold rolling etc. These mechanical heat treatment processes not only affects the mechanical properties of material but also electrical properties also.

Leave a Comment