高温高压环境下高速运动弹带宏观力学特性研究

The rotating band is an important component of the projectile. During the launch of artillery, not only the band will withstand high temperature induced by powder gas,friction and high pressure, high speed friction,but also its material will undergo the process of deformation, flow transition, phase transition and melting. The macroscopic mechanical properties can be characterized by the friction coefficient and the equivalent stiffness. With the utilization of metallurgical analysis techniques, the changes of the band microstructure after the launch will be estimated. According to the results of Hopkinson pressure bar experiments, the law of deformation and failure of the band with high temperature, transient large deformation will be studied and an improved Johnson-Cook model will be proposed to construct the constitutive law of band material. Considering the unsteady melting process of the band material, the high speed sliding friction model between the band and barrel will be proposed. A multi-phase , multi-physics nonlinear dynamic model of standard structure of band will be constructed to reveal the flow transition, phase transition and the melting mechanism of band material, and obtain the dynamic response of the band under the circumstance of different temperature, load , speed et al. Based on the meta-modelling techniques, the equivalent stiffness model which considers the effects of temperature, load, speed and other conditions will be obtained. The band experiment platform of equivalent stiffness which considers the factor of high temperature, high pressure, and high speed will be built to verify its validity. The research project is of great significance to analyze the force and movement of the projectile accurately.

弹带是弹丸的重要部件，伴随发射过程经受高压、高速摩擦以及火药气体和摩擦产生的高温作用，弹带材料经历瞬态大变形、失效、流变、相变、熔化过程，其宏观力学特性可用摩擦系数和等效刚度表征。本项目应用金相分析技术，推断发射后弹带材料组织形态变化；根据霍普金森压杆（SHPB）实验结果，揭示弹带材料高温、瞬态大变形及失效规律，提出改进Johnson-Cook模型，构建弹带材料本构关系；考虑弹带材料非稳态接触熔化，建立弹带与身管高速摩擦模型；建立标准弹带结构多相多场非线性动力学模型，揭示弹带材料瞬态大变形、流变、相变及熔化机理，获得不同温度、载荷、速度等条件下的动态响应规律；基于代理模型技术，获得考虑温度、载荷、速度等条件的标准弹带结构等效刚度模型；搭建高温、高压、高速环境下标准弹带结构等效刚度实验平台，验证等效刚度模型的正确性。该项目的研究对精确分析弹丸膛内受力和运动规律具有重要意义。

弹炮耦合是火炮设计领域的前沿，弹丸膛内运动过程中弹带是始终与身管接触的部件，其宏观力学性能对弹丸的膛内运动状态有重要影响。弹带身管的相互作用包括弹带的瞬态大变形、弹带与身管的高压高速摩擦作用，涉及弹带的几何、材料和边界非线性的高度复杂动态力学行为。本项目针对上述关键技术难点，紧紧围绕项目预定研究内容和目标，按照时间表有计划、有系统地展开研究，较好地完成了各阶段各项预定研究内容和指标，并在若干方面进行了拓展。主要在高温、高压环境下弹带与身管高速摩擦机理、弹带-身管-火药气体多相多场瞬态非线性耦合、标准弹带结构的设计及等效刚度特性三个方面获得研究进展。在相关理论和方法的基础上，建立了弹带材料高速摩擦和高温、大变形、高应变率动态本构模型，并研制了高压、高速摩擦实验系统，较好地解决了弹带瞬态大变形机理复杂等带来的技术难点。另外，本项目理论成果经过进一步深化和拓展后，未来也可应用于工程机械、航空航天、国防特征装备等其他相关工业领域。项目执行期间，共发表和接收学术论文23篇，其中SCI收录5篇，EI收录18篇。论文发表在本领域的一系列权威学术刊物上，如Nonlinear Dynamic（1篇），Mechanism and Machine Theory（1篇），Acta Mechanics（1篇），兵工学报（5篇）等；1本中文专著；申请发明专利11项，软件著作权5项。该项目的理论成果有力地支撑了负责人承担的国防973（XXX提高XXX理论）和4型火炮型号（均为总师）的研制，包括国内XXX型155毫米车载加榴炮、XXX型122毫米车载加榴炮、XXX型猛士底盘122毫米车载加榴炮以及外贸XXX型155毫米车载加榴炮等。