//example-5.8 //page no-159 //given //ASTM no of grains ASTM=5 //area density of grains N=2^(ASTM-1) //grains/inch^2 at magnification of 100* //as we know that lineal and areal magnification are related as //*100 lineal=*10000 areal //therefore Nnew=N/0.01/0.01 //grains/inch^2 at 1* //average area of one grain A=1/Nnew*(2.54)^2 //cm^2 //now 160000 grains/inch^2 of surface is sqrt(160000)=400 grains/inch of length and this is equal to=(400)^3==6.4*10^7 grains/m^3 of volume //surface area of each cubic surface S=(1/400)^2 //inch^2 //there are 6 surfaces in accubic grain //thus total surface area of each grain T=1/2*6*S*(400)^3/2.54 //cm^2 boundary per cubic cm of steel printf ("the boumdary area per cubic centimeter of steel is %f cm^2 boundary per cubic centimeter of steel",T)