研究了一步淬火配分(Quenching and partitioning,Q&P)和两步Q&P工艺对430铁素体不锈钢微观组织与力学性能的影响。结果表明,经两步Q&P处理后,430铁素体不锈钢形成了铁素体、马氏体和残留奥氏体复相组织;而经一步Q&P工...研究了一步淬火配分(Quenching and partitioning,Q&P)和两步Q&P工艺对430铁素体不锈钢微观组织与力学性能的影响。结果表明,经两步Q&P处理后,430铁素体不锈钢形成了铁素体、马氏体和残留奥氏体复相组织;而经一步Q&P工艺处理后,仅形成铁素体和马氏体双相组织。在一步Q&P工艺中,由于碳原子的扩散速率较低,无论是调控配分时间还是配分温度,均未能使残留奥氏体稳定保留至室温。经一步Q&P工艺处理后,试样的强塑积范围为9.3~11.4 GPa·%,而经过两步Q&P工艺处理后,试样的强塑积为17.0 GPa·%。残留奥氏体的存在显著提升了材料的塑性和强塑积。尽管一步Q&P工艺具有简便高效的优势,但并不适用430铁素体不锈钢的性能优化。展开更多
Accurate simulations of ultra-wideband （UWB） electromagnetic radiation from an antenna were developed based on a time-domain finite element method （TDFEM） based on p-step Lagrange interpolation for the temporal ex...Accurate simulations of ultra-wideband （UWB） electromagnetic radiation from an antenna were developed based on a time-domain finite element method （TDFEM） based on p-step Lagrange interpolation for the temporal expansion. The motivation was to utilize the good interpolation features and straightforward computations for UWB antenna simulations. Numerical results were obtained from the cases of the cavity resonance problem, a bowtie and a Sierpinski bowtie antenna. Comparisons with an existing TDFEM approach employed linear temporal basis functions show good agreement to demonstrate the validity of the present schemes. The TDFEM with 2-step Lagrange interpolation as the temporal basis functions achieves better numerical results with only a small increase to run time and memory use in terms of the relative errors of the resonant frequency in the cavity for the transverse electric mode and the radiation patterns of the bowtie antenna.展开更多
文摘研究了一步淬火配分(Quenching and partitioning,Q&P)和两步Q&P工艺对430铁素体不锈钢微观组织与力学性能的影响。结果表明,经两步Q&P处理后,430铁素体不锈钢形成了铁素体、马氏体和残留奥氏体复相组织;而经一步Q&P工艺处理后,仅形成铁素体和马氏体双相组织。在一步Q&P工艺中,由于碳原子的扩散速率较低,无论是调控配分时间还是配分温度,均未能使残留奥氏体稳定保留至室温。经一步Q&P工艺处理后,试样的强塑积范围为9.3~11.4 GPa·%,而经过两步Q&P工艺处理后,试样的强塑积为17.0 GPa·%。残留奥氏体的存在显著提升了材料的塑性和强塑积。尽管一步Q&P工艺具有简便高效的优势,但并不适用430铁素体不锈钢的性能优化。
文摘Accurate simulations of ultra-wideband （UWB） electromagnetic radiation from an antenna were developed based on a time-domain finite element method （TDFEM） based on p-step Lagrange interpolation for the temporal expansion. The motivation was to utilize the good interpolation features and straightforward computations for UWB antenna simulations. Numerical results were obtained from the cases of the cavity resonance problem, a bowtie and a Sierpinski bowtie antenna. Comparisons with an existing TDFEM approach employed linear temporal basis functions show good agreement to demonstrate the validity of the present schemes. The TDFEM with 2-step Lagrange interpolation as the temporal basis functions achieves better numerical results with only a small increase to run time and memory use in terms of the relative errors of the resonant frequency in the cavity for the transverse electric mode and the radiation patterns of the bowtie antenna.
