Injection molding is one of the essential production processes in the processing of plastics into components. The thermoplastics used in this process are divided into amorphous and semi-crystalline solidification on the basis of their properties. In the case of semi-crystalline plastics, crystallization nuclei form below the crystallization temperature, from which spherulitic structures grow. The temperature regime in the injection molding process influences the degree of crystallization and the microstructure in such a way that, depending on the process conditions, high or low degrees of crystallinity or fine or coarse microstructures are formed, which are also additionally influenced by shear. The degree of crystallization in turn influences the properties of the semi-crystalline plastic. Depending on the application, a certain morphology can thus be advantageous in relation to a complete component, but also only in individual areas. The aim of this study is therefore to provide scientific evidence of the manufacturability of a selectively adjustable degree of crystallinity within a functional component made from a semi-crystalline plastic in an injection molding process. The relationship between temperature control in the process, heating and cooling rates and crystallinity as well as morphology should be investigated using the semi-crystalline materials POM, PBT, PPS, PP, PET, PA66 and PA6. The starting point was the development of an article geometry and mold concept adapted to the intended manufacturing process (injection molding with variothermal tempering) and the intended analysis methods (DSC, DMA, short-term tensile test, polarization microscopy). According to current findings, it can be stated that at least the morphology/spherulite size and the degree of crystallinity can be influenced in the injection molding process if suitable process conditions are selected, whereby the material properties can be changed accordingly.