Aiming at the problem of the weld fatigue test of the new energy vehicle subframe, a program load spectrum compilation method based on the failure dominant load was proposed. Firstly, the finite element model of the rear subframe was established, and the stress distribution under unit load was coupled with the load of each connection point. The structural stress method was used to evaluate the fatigue life of the subframe welds, and six dangerous points that were easy to fail were selected. Secondly, by comparing the load damage of each connection point, the failure dominant connection point corresponding to the weld dangerous unit was determined. Then, the failure dominant load was determined by the principal stress analysis, time domain correlation and uniaxial damage contribution at the weld, so as to reduce the dimension of the multi-axial load and reduce the difficulty of the bench test loading. Finally, a pseudo-damage matrix was output based on the failure dominant load, the characteristic working conditions and their proportions were selected to obtain the load spectrum of the fatigue accelerated test program, and the minimum number of cycles was determined according to the principle of the damage equivalence. The numerical simulation results show that the program load spectrum can reproduce the damage of dangerous points and has a high acceleration coefficient, which verifies the effectiveness of the accelerated test spectrum.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |