汽车铝应用手册_AAM_body-components_2.pdfVIP

Applications – Car body – Body components Table of contents 2 Body components and modules 2 2.1 Engine cradles and engine mounts 2 2.2 Suspension strut domes 8 2.3 Front end carriers 12 2.4 Cross car beam (instrument panel support) 13 2.5 Rear frame 16 2.6 Other aluminium components in the body structure 17 Version 2013 © European Aluminium Association (auto@eaa.be) 1 2 Body components and modules Structural aluminium components and modules can be safely integrated into a steel body structure. There are different methods for joining aluminium to steel which fulfil highest requirements. However, when the integration of structural aluminium components and modules into a steel body structure is considered, solutions must be sought for two issues: - Aluminium/steel joints have to be designed and/or properly protected to safely avoid any possibility of galvanic corrosion. - Potential problems due to the different thermal expansion coefficients of steel and aluminium must be accounted for in the design process. Proven and tested corrosion protection methods are readily available. The necessary precautions depend on the specific application and the selected joining technique, but when the proper measures are taken, long term performance of the assembled mixed material structure can be guaranteed. Thermal expansion effects are of little relevance under normal service conditions. Thus, the installation of structural aluminium components and modules into the lacquered body-in-white (BIW) presents in general no problems. More difficult is the integration of aluminium components into a steel body structure in the body shop, i.e. ahead of the lacquering operation of the BIW. In this case, it is essential to prevent (or minimize) the formation of residual internal stresses or the occurrence of geometrical distortions due