选区激光熔化Ti-6Al-4V粉末氧含量的在线监测

Online Monitoring of Oxygen Content in Powder of Ti-6Al-4V Powder in Selective Laser Melting

选区激光熔化中金属粉末的循环利用是该技术的重要研究课题之一,其中粉末氧含量是决定粉末是否可重复利用的关键参数。选取Ti-6Al-4V粉末作为研究对象,使用设计的熔池光辐射检测系统,实现了粉末氧含量的在线监测。其中,检测系统中设计并使用了复合结构的专用放大电路,能够有效检测微弱且变化快的熔池辐射光信号。实验结果表明,氧含量分别为0.09wt.%和0.13wt.%的两种粉末在580nm和590nm波长下的辐射光信号有明显差异,且两个波长下的信号之比可用于区分两种不同氧含量的粉末。

Recycling of metal powder in selective laser melting is one of the important research topics of this technology.The oxygen content of powder is the key parameter to determine whether powder can be reused or not.In this paper,Ti-6Al-4V powder is selected as the research object,and the online monitoring of powder oxygen content is realized by using the designed melton pool light radiation detection system.Moreover,the special amplifying circuit of composite structure is designed and explored in the detection system,which can effectively detect the weak and fast changing light signal of molten pool radiation.The experimental results show that the radiattion light signals of the two powders with oxygen content of 0.09wt.%and 0.13wt.%at the wavelength of 580nm and 590nm are obviously different,and the signal ratio of the two wavelengths can be used to distinguish the two powders with different oxygen content.