Polyamide blends composed of PA 46 and PA 6I were melt-mixed using a double-screw extruder, and the obtained compounds were subsequently processed by injection molding. The blend materials obtained were found to have undergone transamidation processes during the extrusion and injection-molding operations which alter the crystallization and melting behavior. The variation in thermal behavior is strongly dependent on the change in the average sequence length of the crystallizable component in the copolymer formed; it is affected by the compounding and processing conditions and by the blend composition. The influence of every melt-processing step on the crystallization and melting behavior of the blends was investigated by thermal analysis using extruded, injection-molded, and solution-prepared blends.