The phenomena involved during equiaxed growth are dynamic, so that in situ and real-time investigation by X-ray imaging is compulsory to fully analyse the microstructure formation. The experiments on Al – 10 wt% Cu alloy of this paper are carried out at the European Synchrotron Radiation Facility (ESRF) in Grenoble (France). Equiaxed growth was achieved in nearly isothermal conditions and continuously monitored from the very early stages of solidification to an asymptotic state. First, measurements of dendrite arms velocity for a same grain showed slight differences in the early stages of the growth. This effect is attributed to a gravity-related “self - poisoning” of the grain. Then, the propagation of primary dendrite arms was analysed and two successive growth regimes were observed. First, due to the relative distance with neighbour grains, each grain could be considered as isolated (i.e.growing freely) and tip growth rate gradually increased. In a subsequent phase, tip growth rate slowly decreased towards zero, due to the proximity of neighbouring grains. Using an image analysis technique, we were able to measure the solute profiles in the liquid phase between interacting arms. These measurements confirmed that solutal impingement is responsible for stopping the grain growth.