电子束熔覆大面积均匀束斑设计及试验

文中利用角度等分和热作用等分原理,通过理论计算设计出投影波形束斑模型,该束斑模型具有扫描区域内能量均匀分布的特点.对所设计的投影波形进行离散化处理,利用最小二乘法对波形进行拟合,生成电子束设备数控系统能够识别的图形.针对常用的典型波形和理论计算的投影波形,分别在铌合金硅化物涂层上进行束斑波形均匀性试验.结果表明,投影波形熔覆处理区域在表面均匀性、表面平整性和表面颗粒均匀性等方面,均优于常用典型波形.

Uniform large area beam spot design and experimental investigation in electron beam cladding process

Based on equal theory of heat and arc,a heat model called theoretical calculation projection figure was designed.The designed projection figure model has a big heat functioned area,and energy distributes uniformly in scanning area.In order to create a figure that electron beam equipment can distinguish,the designed projection figure model was discret and simulated by least square method.Silicide coatings were fabricated by electron beam irradiation with designed projection scanning figure and other typical scanning figure.Then the effect of scanning figure on energy input uniformity was studied by optical microscopy and scanning electron microscopy.The result showed that designed projection scanning figure was suitable for EB cladding process,and better and flatter silicide coating surface was obtained compared with other typical scanning figure.