Minerals and Metals in Ancient India v1.c16.s2.t1.14

v1.c16.s2.t1.14

The microstructure of the metal revealed equiaxial grains and twinning of the grains. The recrystallised grains prove that after casting, the axe was heated above the recrystallisation temperature, about 500°C. Twinning of the grains indicates that it was subjected to intermittent anneals. These thermal and mechanical treatments were given to the object to produce its smooth surface finish and bevell the cutting edge. Absence of strain lines in the microstructure of the butt end of the axe indicates that this portion of the axe was finally annealed. Although the blade end of this Navdatoli axe was not examined, Hegde showed that in a similar bronze axe from Somnath, the cutting edge was finally forged and work hardened while the body was left in an annealed condition.