发射药的装药质量是影响火炮武器作战性能的关键因素,而炸药粉末多为混合粉末。为了提高大长径比混合粉末柱体的等静压成形品质,采用连续体塑性理论描述柱体成形过程的力学行为,分别使用Shima-Oyane模型和Ogden模型作为粉末柱体和橡胶包套的材料本构模型,借助非线性有限元软件MSC.Marc建立了大长径比柱体等静压成形仿真模型,基于该仿真模型探究了柱体的成形机理,对比研究了等静压工艺参数对柱体成形质量的影响规律。结果表明:所建立的仿真模型能很好地反映柱体等静压成形特点;等静压最大压强和最大压强保压时间是影响柱体成形品质的关键因素,当压强达到240 MPa并保压超过400 s时,柱体整体相对密度达到了97%以上,密度分布差在0.5%以下。实验结果验证了仿真分析结果的准确性,长径比约5∶1的柱体达到了较高的工艺标准,满足了工艺需求。

The quality of explosive charge is a key factor affecting the performance of artillery weapons, and the explosive charge is often a mixture of powders. To improve the quality of cylinders made by a mixture of metal and non-metal powders, the mechanical behavior of the cylinders was described using continuum plasticity theory, the Shima-Oyane model and the Ogden model were employed as the material constitutive models for the cylinders and the rubber sleeve, respectively. And a simulation model for the isostatic pressing of cylinders was developed utilizing the nonlinear finite element software MSC.Marc. Based on the simulation model, the forming mechanism of cylinders was explored, and a comparative study was conducted on the influence of isostatic pressing process parameters on the forming quality of the cylinders. The results indicated that the simulation model could effectively reflect the forming characteristics of the cylinders. The maximum pressure and it’s holding time of isostatic pressing were the key factors that influenced the quality of the cylinders. When the pressure was set at 240 MPa and the holding time exceeded 400 s, the overall relative density of the cylinders reached above 97%, with the density distribution difference was below 0.5%. The results of the isostatic pressing experiment verified the accuracy of the simulation analysis results. The cylinders with approximate length-to-diameter ratios of 5∶1 achieved a higher process standard and satisfied the process requirements.