称取0.2g纯铁助熔剂于处理好的坩埚中,加入0.2g样品,再在上面覆盖1.3g钨粒、0.2g锡粒覆盖,设置截止燃烧时间为35s,建立了三元助熔剂熔融-高频燃烧红外吸收法测定铝钛碳中间合金中碳的方法。实验表明:方法空白平均值w(C)=0.000 8%(n=5),与所测铝钛碳中间合金样品中的碳质量分数范围0.10%~0.30%相比可忽略不计。方法用于铝钛碳中间合金实际样品中碳的测定,结果与管式炉燃烧-碱石棉吸收重量法相符,相对标准偏差(RSD,n=10)为0.54%~0.71%,加标回收率为98%~101%。适用测量碳质量分数的范围为0.10%~0.30%。
0.2 g of pure iron fluxing agent was put into the treated crucible. Then, 0.2 g of sample was added and covered by 1.3 g of tungsten particles and 0.2 g of tin particles. The combustion time was set at 35 s. Thus,a determination method of carbon in aluminum-titanium-carbon master alloy was established by high frequency combustion infrared absorption method after fusion with ternary flux. The results showed that the average blank value of the proposed method was w(C)=0. 000 8G (n=5), which could be ignored compared with the mass fraction of carbon ranged from 0.10~/00 to 0.30o//oo in aluminum-titanium- carbon master alloy. The proposed method was applied to determination of carbon in actual sample of alu- minum-titanium-carbon master alloy. The results were consistent with those obtained by tube furnace com- bustion-alkali asbestos absorption gravimetric method. The relative standard deviations (RSD, n= 10) were between 0.54% and 0. 71%. The recoveries of standard addition were between 98%and 101%. This method was applicable for determination of the carbon mass fraction in range of 0.10%-0.30%.