| With the rapid development of China’s aerospace industry,the demand for large and medium-sized components is increasing rapidly.It is urgent to master the independent R&D and production capacity.For large parts in aerospace,most of them are forged,so it is very important to choose the appropriate forging scheme.In this paper,hammer die forging and hydraulic die forging are designed for a certain aircraft beam joint,and the formability,influence on the die,stability and technical economy of the two forging schemes are studied and analyzed.The main contents and achievements of this paper are as follows:(1)The design of beam joint hammer die forging and hydraulic die forging program.Firstly,according to the characteristics of hammer forging and hydraulic die forging,the forgings,technological processes and dies of hammer forging and hydraulic die forging are designed respectively,and the corresponding equipment and blanking specifications are selected.Then the finite element model is established to simulate the forging process.Finally,hammer forgings and hydraulic die forgings with perfect filling and uniform flying edge were obtained.In addition,the variation of temperature and equivalent strain with time of typical cross sections of hammer die forging and hydraulic die forging during pre-forging are analyzed.Temperature and equivalent strain of hammer die forging process change step by step with time,while hydraulic die forging process changes curve.(2)The filling ability of the two forging schemes is analyzed.Both schemes have their advantages and disadvantages.The pre-forging filling of hammer die forging is unsatisfactory,but the filling of final forging is full and the flying edge is uniform,while the hydraulic die forging is full,but the flying edge is not as uniform as that of hammer die forging;The equivalent strain variance of each process is calculated.Equivalent variances of pre-forging and final forging of hammer-top die forging schemes are 0.286896 and 0.10784,respectively.Equivalent variances of pre-forging and final forging of hydraulic die forging schemes are 0.15911 and 0.12706,respectively.On the whole,the deformation uniformity of die forging process of hydraulic die forging schemes is better;It is analyzed that the temperature field of typical cross-section changes with time under the same deformation amount.The temperature distribution of hammer forging is not uniform,and the temperature drop is serious,which is not conducive to forming.(3)The influence of die forging process of two forging schemes on die is analyzed.The die stress and wear of the two forging schemes after die forging are compared and analyzed.The results show that the die stress of hammer forging is obviously larger than that of hydraulic forging,and there are many high stress zones.However,the wear of the two forging schemes is not very different,and the distribution is different according to their own forming differences.(4)The stability of two forging schemes is analyzed.Hammer die forging scheme,free forging billet,size is difficult to guarantee,human factors have great influence,die forging equipment precision is low,fire number is many,process is long,but flexibility is strong,can be used for product trial production;hydraulic die forging scheme,tooling billet,human factors have little influence,die forging equipment precision is high,fire times is less,suitable for mass production.(5)The technical economy of the two forging schemes is compared.The forging weight of hammer forging scheme is 75 Kg,the cost of single piece is 65100,and the material utilization ratio is 70.75%.The forging weight of hydraulic forging scheme is 64 Kg,the cost of single piece is 58400,and the material utilization ratio is 76.19%.Compared with the hammer forging,the hydraulic forging scheme is more lean,low cost,high material utilization ratio and strong technical economy. |
