Search Results

A method of developing more representative test factors and respective minimum cycles is proposed in practices such as J328 and J2530. The method includes recent 6061-T6 material fatigue characterization from specimens originating in wheels. The characterization uses a fully reversed (R=−1) loading method and the specimen is in un-notched condition. Results of finite element analyses of different wheel designs are observed to verify the proposition of usage of R= −1 as appropriate for such material characterization. The results of recent fatigue response of 6061-T6 indicate that the accelerated test load factors found in SAE J328 and SAE J2530 can be reduced by 10%, while rendering at least the same structural margin as that of other ferrous and nonferrous materials. SAE J2562 illustrates a methodology for testing the structural adequacy of a wheel design using loads and cycles that more closely replicate on-vehicle service than those of J328 and J2530.

A wheel load history was provided for front and rear positions of a sport car under service that included motorsport track and public road service. Biaxial load files are developed from the wheel load histories. A wheel load history is the combination of cycles and respective load pairs whose sum is the expected life of the vehicle. An alternate process to SAE J2562 is used to reduce wheel load history to a biaxial load file with equivalent fatigue damage. The contents of the load file were used to calculate life prediction using finite element and fatigue analyses. Wheels were then tested on the biaxial test machine to establish correlation with simulation predictions. Since the wheel designs are unique between front and rear positions, the biaxial fatigue files are developed and maintained similarly unique to position. Correlation between simulation prediction and biaxial fatigue tests has been confirmed.