[en] Dynamic recrystallization was investigated using a high purity model material, with a composition near that of AISI 304L austenitic stainless steels. Interrupted uniaxial compression tests were performed at 850 deg C and 10^-3 s^-1. Under such conditions, dynamic recrystallization leads to grain refinement and is associated with a single peak stress-strain curve. A decrease of grain size by a factor of 3 from the initial (ε = 0) to the steady state (ε = 0) to the steady state (ε = 1,5) is observed. The typical necklace nucleation mechanism appears at a strain of 0.4 and causes noticeable softening. Inhomogeneities from grain are quite apparent: in 'young' grains, internal mis-orientations are limited, while twins are systematically detected; by contrast, in 'old' grains, an internal substructure is visible, whereas twins have transformed into normal grain boundaries. At the steady state, the microstructure is made of mixture of old and new grains and there is no obvious correlation with their sizes. The steady state distribution of grain seems to be close to that of the initial state. (authors)