Al元素挥发的影响
(西北有色金属研究院 钛合金研究所,西安 710016)
摘 要: 研究不同熔炼工艺参数对电子束冷床熔炼TC4钛合金过程中Al元素挥发的影响规律。结果表明:原料为真空自耗电弧(VAR)一次锭时,二次铸锭经电子束冷床熔炼获得;在轴向上,从铸锭的顶部至底部,Al元素的含量呈下降的趋势,并且随着熔炼速度的降低,其下降趋势更为明显;在径向上,铸锭的元素分布均匀。熔速为100 kg/h时,铸锭成分控制效果最佳,最接近TC4合金的名义成分。初始原料为电极块(添加单质Al)时,Al元素在原料熔化阶段发生较严重的挥发,且挥发量随着原料中单质Al含量的增加而增加。研究凝壳发现,从原料熔化侧至钛液流出侧,凝壳中Al元素的含量逐渐减少。
关键字: 电子束冷床;TC4钛合金;熔炼工艺参数;Al元素挥发
Al element evaporation in TC4 titanium alloy
(Titanium Alloy Research Center, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China)
Abstract:The effects of different melting process parameters of electron beam cold hearth on the Al element evaporation in TC4 alloy was studied. The results show that when the raw material is the VAR ingot, the secondary ingot is got by EBCHM. In the axial direction of the ingot from the top to the bottom, the Al content presents a decrease trend, and as the melting rate decreases, the decrease trend is more evident. In the radial direction of the ingot, the alloy element distribution is very uniform. When the melting speed is 100 kg/h, the ingot composition control is the best, and the composition is the closest to the name components of TC4 alloy. When the raw material is the simple substance Al, the element evaporation loss increases in the melting stage, and it increases with the Al content increasing. Research of the skull founds that, from the raw materials melting side to the titanium liquid outflow side, the Al content decreases.
Key words: electron beam cold hearth; TC4 titanium alloy; melting process parameters; Al element evaporation