The distribution of doping elements and impurities between the external surfaces and internal volumes of typical fine particles in samples of gas-atomized commercial additive powders of hightemperature creep-resistant (Inconel 939, ZhS32) and high-temperature oxidation-resistant (Inconel 625, Hastelloy C22) nickel superalloys was examined employing energy-dispersive X-ray analysis (EDX). Significant concentration gradients were observed between the surfaces and internal volumes of powder particles for doping elements reaching 4–5 wt.%: Re, Mo Ta, and Nb in the high-temperature creep-resistant alloys and Al, Nb, Co, Fe, V, and Mn in the Inconel 625 hightemperature oxidation-resistant alloy. Besides doping elements, concentration gradients of O, N, S, P, and Si impurities were found in the near-surface layers of the additive powders. The EDX findings and data from the reduction–extraction method were used to calculate the amounts of oxygen and nitrogen in the internal volumes and the near-surface layer of typical fine powder particles and the thickness of this layer corresponding to the increased content of impurities. The surface layer of typical fine particles was shown to increase the total weight-average content of impurities in the samples of commercial additive powders: oxygen up to 2.5 times and nitrogen up to 1.8 times. To assess the influence of impurity amounts of oxygen <0.16 wt.% and nitrogen <0.13 wt.% on the welding process properties of the atomized additive powders, additional samples of hightemperature oxidation-resistant (ChS40) and high-temperature creep-resistant (ZhS6U, ZhS32, Renè 80) nickel superalloys were tested to ascertain their suitability for microplasma powder deposition at a welding current of up to 15 A. It was found that the suitability of the additive powder for lowamperage deposition was mainly determined by the limited oxygen impurity content: weight-average content up to 0.025 wt.% and content in the 1–3 μm thick near-surface layer of a typical fine particle up to 0.1 wt.%.

高温抗蠕变（Inconel 939、ZhS32）和高温抗氧化（Inconel 625、Hastelloy）气雾化商业添加剂粉末样品中典型细颗粒的外表面和内部体积之间的掺杂元素和杂质的分布采用能量色散 X 射线分析 (EDX) 对 C22) 镍高温合金进行了检查。当掺杂元素达到 4-5 wt.% 时，在粉末颗粒的表面和内部体积之间观察到显着的浓度梯度：高温抗蠕变合金中的 Re、Mo、Ta 和 Nb 以及 Al、Nb、Co、Fe、 Inconel 625高温抗氧化合金中的V、Mn。除了掺杂元素外，在添加剂粉末的近表面层中还发现了 O、N、S、P 和 Si 杂质的浓度梯度。EDX 结果和还原萃取法数据用于计算典型细粉颗粒内部体积和近表面层中氧和氮的含量，以及与杂质含量增加相对应的该层的厚度。研究表明，典型细颗粒的表面层会增加商业添加剂粉末样品中杂质的总重均含量：氧气高达 2.5 倍，氮气高达 1.8 倍。为了评估氧杂质含量<0.16 wt.%和氮杂质含量<0.13 wt.%对雾化添加剂粉末焊接工艺性能的影响，附加了高温抗氧化（ChS40）和高温抗蠕变（对 ZhS6U、ZhS32、Renè 80) 镍高温合金进行了测试，以确定其在焊接电流高达 15 A 的情况下对微等离子体粉末沉积的适用性。结果发现，添加剂粉末对低电流沉积的适用性主要取决于有限的氧杂质含量：重均含量高达 0.025 wt.%，典型细颗粒 1–3 μm 厚的近表面层含量高达 0.1 wt.%。