A method to quantify regular graphite and turbo-stratified graphite (TS-graphite) forming the free carbon in ductile cast iron was developed using X-ray powder diffractometry. Iron in accurately sampled 2–4 g of the ductile cast iron powder was decomposed using hydrochloric acid without heating, and the residue was centrifugally separated. Graphite, TS-graphite, wustite (FeO), and amorphous silicate were identified in the residue. Calibration-standard mixtures were prepared by mixing corundum (α-Al₂O₃), griceite (LiF), and graphite powder which showed the most similar full-width at half-maximum value of (002) line to that of graphite in the ductile cast iron sample. The calibration curve of graphite showed good linearity, with a range of 0–200 mg corresponding to the 0–5.0 mass% of graphite in the 4.00 g of the cast iron sample. The quantitative value of total graphite in the ductile cast iron sample was 3.17 mass% with 8.0% of relative standard deviation for n = 5. The peak area ratio of graphite and TS-graphite was calculated using Rietveld refinement by assuming the same atomic scattering factor for each graphite measurement. The concentration ratio of graphite and TS-graphite were 67.8 and 32.2%, respectively. The analytical values of graphite were in good agreement with those of the NIST gray cast iron standard material, with concentration ratio of 53.7% and 46.3% for graphite and TS-graphite, respectively.

使用 X 射线粉末衍射法开发了一种量化形成球墨铸铁中游离碳的规则石墨和涡轮分层石墨 (TS-石墨) 的方法。在不加热的情况下使用盐酸分解精确取样的 2-4 g 球墨铸铁粉末中的铁，并将残留物离心分离。在残留物中鉴定出石墨、TS-石墨、方铁矿 (FeO) 和无定形硅酸盐。通过混合刚玉 ( α -Al ₂ O ₃)、石墨粉 (LiF) 和石墨粉，其 (002) 线的半峰全宽与球墨铸铁样品中石墨的半峰宽最相似。石墨的校准曲线显示出良好的线性，范围为 0-200 mg，对应于 4.00 g 铸铁样品中 0-5.0 质量％的石墨。球墨铸铁样品中总石墨的定量值为3.17质量%，n的相对标准偏差为8.0%= 5. 石墨和 TS-石墨的峰面积比是使用 Rietveld 细化计算的，假设每次石墨测量具有相同的原子散射因子。石墨和TS-石墨的浓度比分别为67.8%和32.2%。石墨的分析值与 NIST 灰铸铁标准材料的分析值非常吻合，石墨和 TS-石墨的浓度比分别为 53.7% 和 46.3%。