Evolution of the primary components of the massive binary stars in the ofRoche lobe overflow after main-sequence evolution.

The evolution of primary components with 32 and 64 solar masses is studied. Evolving with matter mixing in the semiconvective zone and filling their Roche lobes, these components overflow their Roche lobes after the main-sequence evolution and lose matter during the first part of helium core burning. After the end of the overflow, the components lose their matter as a result of stellar wind and shrink in the nuclear timescale. At first, they have the characteristics of blue supergiants with an anomalous CNO abundance, and then the features of the Wolf-Rayet stars.