History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c13.s2.t12.1

v1.c13.s2.t12.1

With the discovery of the effect of carbon on the properties of iron has begun the real industrial and cultural revolution in this World. The solid state of Iron-carbon phase diagram has been already shown and the effect of ‘C’ on the proportion of Ferrite and cementite phases in the alloy has been already discussed. Ancient Indian iron craftsmen had learnt about the role of carbon in increasing the strength and hardness of iron even as early as Vedic period if not earlier and by 8th to 12th century A.D. they were capable of producing a variety of Iron- carbon alloys as classified in Fig. 32. Yuktikalpataru a Sanskrit alchemical literature of 11 century A.D. mentions the relative properties of iron-carbon alloys as produced in different regions of India and the resulting properties of the alloy produced either due to minute difference in the smelting practice or presence of some other minor alloying elements. The description given in this literature is quoted below: