10 Important differences between Cold working and Hot working

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Following are the 10 important differences between cold working and hot working Working of metal and alloy below their recrystallization temperature is known as cold working , and working of metal and alloy above their recrystallization temperature is known as hot working . During cold working strain hardening occurs and due to this tensile strength, hardness increases while the impact strength and ductility decreases, whereas, due to hot working strain hardening is removed by recrystallization. Microstructure of cold worked component shows distorted grains, whereas, microstructure of hot worked components shows equiaxed and usually refined grains. Due to cold working defect density increases i.e. vacancies, dislocations, etc. increases and hence the density of material slightly decreases, whereas, due to hot working there is almost no change in defect density of material. Cold working cannot be done indefinitely without cracking of material due to strain hardening, whereas, ho
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DIFFUSION DEFINITION

Metallurgical definition of diffusion:

THEORY:

Diffusion is basically the movement of atoms due to the presence of concentration gradient i.e. movement of atoms from a region of higher concentration to a region of lower concentration.

We can also define diffusion in terms of the difference in chemical potentials i.e diffusion is basically the movement of atoms from the region of higher chemical potential to a region of lower chemical potential.

Thus we can say that diffusion is possible both due to the chemical potential gradient as well as due to the concentration gradient.


 CONCLUSION:
Final Definition for DIFFUSION in metallurgy terms:
Diffusion is defined as the movement of atoms in the lattice either interstitially or substitutionally because of the presence of concentration gradient or chemical potential gradient.

Please feel free to ask questions in comments!!!

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10 Important differences between Cold working and Hot working

Image
Following are the 10 important differences between cold working and hot working Working of metal and alloy below their recrystallization temperature is known as cold working , and working of metal and alloy above their recrystallization temperature is known as hot working . During cold working strain hardening occurs and due to this tensile strength, hardness increases while the impact strength and ductility decreases, whereas, due to hot working strain hardening is removed by recrystallization. Microstructure of cold worked component shows distorted grains, whereas, microstructure of hot worked components shows equiaxed and usually refined grains. Due to cold working defect density increases i.e. vacancies, dislocations, etc. increases and hence the density of material slightly decreases, whereas, due to hot working there is almost no change in defect density of material. Cold working cannot be done indefinitely without cracking of material due to strain hardening, whereas, ho
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