低合金钢酸溶铝和酸溶钛含量的测定 电感耦合等离子体原子发射光谱法的验证
王文焱
(河北钢铁股份有限公司唐山分公司)
摘要 :在一些品种钢的冶炼中,多使用铝质脱氧剂,此外铝、钛还作为合金元素添加到钢中,改善钢的组织性能,因此快速准确测定品种钢中酸溶铝和酸溶钛的含量很重要,然而GB/T20125-2006国家标准方法中缺失了酸溶铝质量分数在0.01%~0.02%和酸溶钛0.02%~0.025%含量范围的测定,造成方法中酸溶铝质量分数在0.004%~0.10%和酸溶钛0.001%~0.025%含量范围出现了断续。本方法通过建立新校准曲线将酸溶铝0.01%~0.02%和酸溶钛0.02%~0.025含量范围涵盖,弥补上述方法的缺陷,并对此范围的标准样品进行测定,从而验证了方法的准确度,精密度;通过方法的检出限,样品的基体等特性对检测方法进行验证,并满足了实验室认可准则的要求。表1 短期稳定性、长期稳定性、分辨率的测定值
分析元素 | 分析线/nm | 短期稳定性/% | 长期稳定性/% | 分辨率/nm |
Si | 251.611 | 0.64 | 0.57 | 0.014 |
288.158 | 0.74 | 0.57 | 0.018 | |
Mn | 257.610 | 0.57 | 0.37 | 0.010 |
260.568 | 0.62 | 0.30 | 0.012 | |
Ni | 231.604 | 0.30 | 0.23 | 0.014 |
Cr | 267.716 | 0.63 | 0.56 | 0.017 |
Mo | 202.031 | 0.38 | 0.65 | 0.009 |
Cu | 327.393 | 0.85 | 0.86 | 0.017 |
V | 311.071 | 0.32 | 0.74 | 0.020 |
309.310 | 0.33 | 0.70 | 0.019 | |
Co | 228.616 | 0.54 | 0.50 | 0.014 |
Ti | 334.940 | 0.34 | 0.72 | 0.017 |
337.279 | 0.38 | 0.75 | 0.018 | |
Al | 394.401 | 0.62 | 0.47 | 0.025 |
396.153 | 0.79 | 0.36 | 0.013 |
表2 背景等效浓度和检出限
分析元素 | 分析线/nm | BEC/(mg/L) | DL/(mg/L) | ||
标准规定值 | 测得值 | 标准规定值 | 测得值 | ||
Si | 251.611 | 0.8 | 0.176 | 0.04 | 0.036 |
288.158 | 1.2 | 0.387 | 0.06 | 0.024 | |
Mn | 257.610 | 0.6 | 0.009 | 0.02 | 0.004 |
260.568 | 1.4 | 0.186 | 0.05 | 0.006 | |
Ni | 231.604 | 1.5 | 0.163 | 0.04 | 0.029 |
Cr | 267.716 | 1.9 | 0.001 | 0.05 | 0.003 |
Mo | 202.031 | 1.3 | 0.074 | 0.05 | 0.050 |
Cu | 327.393 | 1.0 | 0.003 | 0.09 | 0.006 |
V | 311.071 | 0.4 | 0.030 | 0.07 | 0.004 |
309.310 | 0.7 | -0.207 | 0.02 | -0.004 | |
Co | 228.616 | 1.2 | 0.045 | 0.03 | 0.015 |
Ti | 334.940 | 0.5 | 0.007 | 0.01 | 0.001 |
337.279 | 0.5 | 0.016 | 0.02 | 0.013 | |
Al | 394.401 | 0.6 | 0.082 | 0.03 | 0.012 |
396.153 | 0.7 | 0.029 | 0.02 | 0.006 |
表3 制作校准曲线的标准溶液
元素及波长nm | 标准溶液浓度μg/mL | 加入标准溶液的体积/mL | 相应试样中元素含量(质量分数)/% | |||||
钛337.279 | 4.2.6 | 1.00 | 2.00 | 3.00 | 5.00 | 10.00 | 15.00 | 0.002~0.03 |
铝394.401 | 4.2.3 | 2.00 | 3.00 | 4.00 | 5.00 | 10.00 | 15.00 | 0.004~0.03 |
表4 精密度、准确度
名称 | 标样编号 | 元素波长(nm) | 标准值% | 10次测定结果% | 平均值 | RSD/% |
低合金钢 | GBW01307 | Ti(337.279) | 0.023 | 0.023,0.024,0.023,0.023,0.023,0.023,0.023,0.023,0.023,0.023 | 0.023 | 1.20 |
Al(394.401) | 0.029 | 0.028,0.028,0.027,0.027,0.027,0.027,0.027,0.027,0.027,0.027 | 0.027 | 2.05 | ||
碳素钢 | GSB03-2618-2010 | Ti(337.279) | 0.023 | 0.022,0.022,0.022,0.02,0.022,0.022,0.022,0.022,0.022,0.022 | 0.022 | 1.45 |
Al(394.401) | 0.016 | 0.014,0.015,0.014,0.014,0.015,0.014,0.015,0.013,0.014,0.015 | 0.015 | 2.92 | ||
12MnMoVTiNiB | 6912 | Ti(337.279) | 0.013 | 0.011,0.011,0.011,0.011,0.011,0.011,0.011,0.011,0.011,0.010 | 0.011 | 2.61 |
Al(394.401) |