摘要
电子束扫描工艺影响着铝硅合金熔凝的性能。电子束扫描铝硅合金过程中,会伴随着失重现象,材料的失重对零件的表面形貌以及元素的分布有着直接的影响,进而影响到零件的性能。利用电子束扫描对铝硅合金进行表面熔凝处理,讨论下束时间、扫描频率及功率对表面熔凝处理后试样失重的影响;分析铝、硅两相汽化差异的理论依据,研究飞溅的形成条件,得到失重现象的形成机理。试验结果表明,失重量随着下束时间和功率的增加而加大,快的频率可以抑制失重的进行;饱和蒸汽压值较低的硅相的蒸发量要比铝大;在给定参数下,电子束在试样表面的作用深度可达18.5μm,在6μm处能量达到最大值。电子束熔凝铝硅合金过程中熔池的飞溅以及硅铝相的蒸发是铝硅合金表面失重的主要原因。
AI-Si alloy surface is remelting and solidification by electron beam to study the influence of electron beam scan technology on alloy properties. During the electron beam scanning the AI-Si alloy, the phenomenon of surface weightlessness which could affect the surface morphology of the parts and the distribution of the element would exist in the process. The effects of electron beam parameters such as scanning time, scanning frequency and power on the weightlessness of samples after remelting arc discussed, theory on gasification differences is also analyzed, the formation conditions of splash is studied, the mechanism of weightlessness formation is disclosed. The experiment results show that weightlessness increases as time and power increase. High frequency block the process of weightlessness, the evaporation capacity of Si whose saturated vapor pressure is lower is more than A1. Under the condition of given parameters, the effective depth of sampling surface comes to 18.5 μm, the highest energy is appeared at 6μm.The main reason of A1-Si alloy surface weightlessness are the splash of molten pool when the electron beam remelt AI-Si alloy surface and the evaporation of A1 phase and Si phase.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第2期73-78,共6页
Journal of Mechanical Engineering
基金
广西自然科学基金(2010GXNSFA013028)
广西自然科学基金重点(2012GXNSFDA053026)资助项目
关键词
电子束扫描
铝硅合金
失重
飞溅
Electron beam AI-Si alloy Weightlessness Splash
