METALLOGRAPHY PROCESSStudy of the physical structure and components of metals using light microscope.

2. Mounting

Mounting of specimens is usually necessary to allow sample to be handled easily. A mounted specimen usually has a thickness of about half its diameter, to prevent rocking during grinding and polishing. The edges of the mounted specimen should also be rounded to minimize the damage to grinding and polishing discs.

3. Grinding

Surface layers damaged by cutting must be removed by grinding. Mounted specimens are ground with rotating discs of abrasive paper. Abrasive paper typically ranges from 120 to 1200(Coarse to fine).

4. Polishing

Polishing discs are covered with soft cloth impregnated with abrasive diamond particles and an oily lubricant or water lubricant.

1. Cutting

Large piece of metal should be cut by using diamond saw. Great care should be taken while preparing specimen because cutting with abrasive may cause a high amount of damage . Mechanical damage may change the microstructure of the material.

6. The Sample is Ready for microscopic view

5. EtchingProcess of revealing microstructural details which will not be seen just by polishing.

Aluminum Microstructure