TABLE OF CONTENTS The Dub classification applies equally well to the various morphologies of cementite formed at progressively lower transformation temperatures. The initial development of grain boundary allotriomorphs is very similar to that of ferrite, and the growth of side plates or Widmanst tten cementite follows the same pattern (Figs 3.3e, f). The cementite plates are more rigorously crystallographic in form, despite the fact that the orientation relationship with austenite (found by Pitsch) is a more complex one, i.e.:
As in the case of ferrite, most of the side plates originate from grain boundary allotriomorphs, but in the cementite reaction more side plates tend to nucleate at twin boundaries in austenite.
