Report Requirements Draw the microstructure of the specimen

Report Requirements: Draw the microstructure of the specimen provided by the instructor during the lab session and explain what you have seen. Use the Work Sheet below. Sample # Material: Chemical Composition: Etchant: Etching Time: Magnification: Percentage of existing phases: Grain size:in mu m ASTM grain size no. : Defects (transgranular/intergranular cracks, slags, pores, inclusions, etc) Equilateral or elongated grains? Orientation of grains with respect to each other :

Solution

Solution:

Material : Carbon steel

Chemical composition: 0.29-0.54 % carbon ; 0.6-1.65% manganese

Etchant: Nital (Ethanol + Nitric acid)

Etching Time : upto 1 minute

Magnification: ferrite & cementite

Percentage of existing phase :depends on carbon exact content

Grain size : depend on sample given

it is given by N = 2^(n-1) where N is no of grain in that sample per square inch

& n is ASTM grain no

Rest all 3 could be observed from lab sample only.