In this lesson we're going to focus on the development of bainite that comes out of a eutectoid steel. And we're going to follow the same progress that we did as we did when we described the decomposition of austenite into pearlite. So now here is our eutectoid diagram again, here is the temperature range over which we're interested. We see that first red dot represents the austenite, and the lower temperature is where the bainite is going to begin to form. So, what happens in the case of forming the bainite, which is different than the way the pearlite forms, is basically, we start out with our austenite grain boundaries. And I've indicated these structures that are looking like laths that have grown from the austenite grain boundary in toward the center of the austenite grains. I've shadowed these with some colorant to indicate that around those particles, which turn out to be ferrite, is where the carbon is going. So the carbon is leaving the ferrite and it has a cloud around the individual ferrite structures, and eventually what's going to happen is those clouds will begin to form the Fe3C inside of the bainite lamellar or the bainite structures that we have, the laths of bainite. So there's our carbon clouds. And now what we're going to do is to allow some more time so that these structures begin to form. And we can produce some more of the structure where those that formed initially turn out to begin to have the structure of the ferrite in these little grains, and the cementite that comes out. And at this next time step, what's happened is we have nucleated and grown some more of these alpha phases from the austenite grain boundary. So the austenite supplies the location for where the transformation is going to occur. The alpha phase forms and then we get the distribution of carbon around because of the low carbon content of the ferrite. And then eventually what happens is the ferrite begins to have some precipitation of the phase Fe3C or the iron carbide. And so that's what those little hot dog shaped particles are that are in the structure. So depending upon the cooling rate and the holding temperature, we're going to wind up getting different morphologies of bainite. And as it turns out there are two types of bainites that form, high, upper bainite and lower bainite and the principle difference between the two of these is the fineness of the structure. And so what you find is in the case of lower bainite, those particles of Fe3c are very fine and as a result are going to help contribute to the overall strength of the material that will be the result when all the austenite has decomposed and we're left with this two phase microstructure of alpha ferrite and Fe3c. So when we look at the micrographs we have a micrograph where the bainite form at an elevated temperature 495 C and we have these types needle like structures which are growing into the austenite. And what you begin to see is as you go to a lower temperature, you get the development of very tiny particles inside, and those tiny particles are the ones that are helping to contribute to the strength of the material as a result of their fine distribution. So the structure that we're looking at is given to the left here, where we have the schematic of what the bainite looks like. So these two structures that form, the pearlite morphology that develops and the bainite morphology, both of these develop from the single phase austenite and develop these two different morphologies depending upon the temperature to which they're quenched. Thank you.