钛基合金中氩的分析探讨及应用

Discussion on the determination and application of argon in titanium-based alloy

应用脉冲熔融-质谱/热导法定量分析钛基合金样中氩含量,同时分析了氩释放和氩的宏观偏析。结果表明:不同的制备工艺控制,氩含量差异较大;氩含量的增高未影响氧、氮、氢含量的明显变化,可用于指导工艺;样品中氩在低温释放,以非化合态形式存在。采用飞行时间二次离子质谱仪观察了样品中氩的微观状态,利用力学仪器对比考察了含氩1 000μg/g和1μg/g以下样品在室温、650℃及800℃下的拉伸性能。结果表明:钛基粉末冶金材料中氩质量分数可以高达0.0X%,氩在试验样中宏观偏析不严重,100μm×100μm区域的微观偏析严重。氩以非化合态单质存在于钛基合金内部,形成孔隙类缺陷,对该材料的力学性能产生不良影响。

Pulse fusion-mass spectrometry/thermal conductivity was used to determine quantitatively argon content, argon release and argon macro segregation in titanium based alloy. The results showed that： argon content was obviously different for different preparation technology; the increase of argon content did not influence the content of oxygen, nitrogen and hydrogen, which could be used for technology guidance; argon in the sample was released at low temperature and existed in the uncombined state. The micro state of argon in the sample was observed by time-of-flight secondary ion mass spectrometry. Tensile test was conducted on samples with 1 000 μg/g and below 1 μg/g argon at room temperature, 650 ℃and 800 ℃ by mechanics instrument for contrast. It indicated that the mass fraction of argon in titanium-based powder metallurgical materials could be up to 0.0X% ; macro segregation of argon in the sample was not severe, while micro segregation was severe within 100 μm×100 μm zone. Argon existed in the form of uncombined element in titanium-based alloy, causing pore defects which were harmful for the mechanical properties of the material.