Research Quality Control Of Aluminum Alloy Heavy Forging By Local Loading

Large forgings with T-shape section have wildly applied in the aerospace due to its good comprehensive performance. The investigated part with high belly board belong to typical Rib-Web component. Some defects such as under-filling, grain coarsening, inhomogeneous forming, are always observed in its forging process. Although the loading could be decreased by local forming, its special forming process would cause some defects. To solve those problems for the local forming process, the forging theory, numerical simulation, and artificial intelligence are applied in this investigation. The main conclusions are shown as following:(1) The investigation for the law of material flow in the local forming process with numerical simulation. The flow law of material at different directions is obtained by contrasting Integral and local forming processes. The influence factors, shape of billet, loading sequence, temperature, loading speed, and effective length per reduction are obtained by analyzing the process of material filling in the two steps local forming process.(2) The influence of different factors on quality index are analyzed by using single factor experiment. The rationality of billet are verified. The influence rule of forming quality index, filling behavior, average grain size and the distribution of grain, is studied by single factor experiment for shape of billet, loading sequence, temperature, loading speed, and effective length per reduction.(3) Process parameters of multi-objective optimization of the forging forming based on BP-GA optimization algorithm. A BP-GA model was established, with the filling capacity, average grain size and micro-structural uniformity as its evaluation objectives, also shape of billet, loading sequence, temperature, loading speed, and effective length per reduction were selected as the design variables of that model for the local loading process. then the reasonable solutions were obtained under relatively high accuracy of the model.(4) Trail production. The research results have been applied to the actual production successfully, then a T-shape aluminum alloy forging of good macro and micro quality was obtained.