This work presents a chronological summary of the two theories of the bainite transformation, charting
their progression and noting the variety of evidence both in support of and in contradiction to each viewpoint.
The ‘bainite controversy’ is still debated by steel metallurgists today, although it has mostly been
reduced to the question of whether or not bainitic ferrite initially forms with a supersaturation of carbon.
This review gathers and evaluates some of the accumulated work in the hope that this question may finally
be answered.