电子反流失效模式是离子推力器关键失效模式之一,决定推力器工作寿命。为明确各参数对电子反流失效模式的影响程度,确定加速应力,为地面加速寿命实验验证方案和长寿命优化设计提供数据支持,采用Hybrid-PIC-MCC(Particle in Cell-Monte C...电子反流失效模式是离子推力器关键失效模式之一,决定推力器工作寿命。为明确各参数对电子反流失效模式的影响程度,确定加速应力,为地面加速寿命实验验证方案和长寿命优化设计提供数据支持,采用Hybrid-PIC-MCC(Particle in Cell-Monte Carlo Collision)方法,构建了三栅极系统数值仿真模型。采用模型研究了地面真空舱本底压力、屏栅电压、加速栅电压、屏栅与加速栅间距、屏栅上游等离子体密度和放电室工质利用率等参数的影响敏感度对比。研究结果显示,真空舱本底压力可以作为加速寿命试验的首选加速应力,在推力器结构和工作本征参数中工质利用率为最敏感应力,其次是屏栅电压、屏栅上游等离子体密度、加速栅电压、屏栅和加速栅间距。展开更多
Cu thin films are deposited on Si(100)substrates by neutral cluster beams and ionized cluster beams.The atomic diffusion and interface reaction between the Cu films and the Si substrates of as-deposited and annealed a...Cu thin films are deposited on Si(100)substrates by neutral cluster beams and ionized cluster beams.The atomic diffusion and interface reaction between the Cu films and the Si substrates of as-deposited and annealed at different temperatures(230℃,450℃,500℃and 600℃)are investigated by Rutherford backscatteringspectrometry(RBS)and x-ray diffraction(XRD).Some significant results are obtained on the following aspects:(1)For the Cu/Si(100)samples prepared by neutral cluster beams and ionized cluster beams at V_(a)=0 kV,atomic diffusion phenomena are observed clearly in the as-deposited samples.With the increase of annealing temperature,the interdiffusion becomes more apparent.However,the diffusion intensities of the RBS spectra of the Cu/Si(100)films using neutral cluster beams are always higher than that of the Cu/Si(100)films using ionized cluster beams at V_(a)=OkV in the as-deposited and samples annealed at the same temperature.The compound of Cu3Si is observed in the as-deposited samples.(2)For the Cu/Si(100)samples prepared by ionized cluster beams at V_(a)=1,3,5 kV,atomic diffusion phenomena are observed in the as-deposited samples at V_(a)=1,5 kV.For the samples prepared at V_(a)=3 kV,the interdiffusion phenomenon is observed until 500℃annealing temperature.The reason for the difference is discussed.展开更多
文摘电子反流失效模式是离子推力器关键失效模式之一,决定推力器工作寿命。为明确各参数对电子反流失效模式的影响程度,确定加速应力,为地面加速寿命实验验证方案和长寿命优化设计提供数据支持,采用Hybrid-PIC-MCC(Particle in Cell-Monte Carlo Collision)方法,构建了三栅极系统数值仿真模型。采用模型研究了地面真空舱本底压力、屏栅电压、加速栅电压、屏栅与加速栅间距、屏栅上游等离子体密度和放电室工质利用率等参数的影响敏感度对比。研究结果显示,真空舱本底压力可以作为加速寿命试验的首选加速应力,在推力器结构和工作本征参数中工质利用率为最敏感应力,其次是屏栅电压、屏栅上游等离子体密度、加速栅电压、屏栅和加速栅间距。
基金Supported by the National Natural Science Foundation of China under Grant No 10375028.
文摘Cu thin films are deposited on Si(100)substrates by neutral cluster beams and ionized cluster beams.The atomic diffusion and interface reaction between the Cu films and the Si substrates of as-deposited and annealed at different temperatures(230℃,450℃,500℃and 600℃)are investigated by Rutherford backscatteringspectrometry(RBS)and x-ray diffraction(XRD).Some significant results are obtained on the following aspects:(1)For the Cu/Si(100)samples prepared by neutral cluster beams and ionized cluster beams at V_(a)=0 kV,atomic diffusion phenomena are observed clearly in the as-deposited samples.With the increase of annealing temperature,the interdiffusion becomes more apparent.However,the diffusion intensities of the RBS spectra of the Cu/Si(100)films using neutral cluster beams are always higher than that of the Cu/Si(100)films using ionized cluster beams at V_(a)=OkV in the as-deposited and samples annealed at the same temperature.The compound of Cu3Si is observed in the as-deposited samples.(2)For the Cu/Si(100)samples prepared by ionized cluster beams at V_(a)=1,3,5 kV,atomic diffusion phenomena are observed in the as-deposited samples at V_(a)=1,5 kV.For the samples prepared at V_(a)=3 kV,the interdiffusion phenomenon is observed until 500℃annealing temperature.The reason for the difference is discussed.