It is essential that joints in the design of aluminium based materials be safe and at the desired strength. Specific methods are to be used in welding of these materials. Brazing, that assures joining without changing the material properties, is widely used for this purpose. In this method, quality joining can be achieved, provided the parameters are set up accurately. In this study, joining characteristics of aluminium based composite materials widely used in automotive industry are investigated in detail. Solid models of the parts manufactured by brazing are created using Solidworks software. Hydrostatic loading similar to the real working conditions is applied to these models and stress analysis is performed using ANSYS software. In the samples, joining regions are 2 mm and 2,83 mm in length; and stress distributions are investigated in three groups assuming full, 70% and 50% joining. Stresses arising from loading in the model are below the damage inducing level, but the shape and the length of the joining region are observed to be significant in stress development.