Jing Min1 ，Qu Dexin1 ，Tang Zeyang1 ，Wang Changdong2 ，Zhang Dejin2 ，Qiao Zhenxing2 ，Sun Jing2 ，Gai Guosheng3
1. School of Materials Science and Engineering， Shandong Jianzhu University， Jinan 250101， China；
2. Shandong Luyin New Material Technology Co. ， Ltd. ， Jinan 271104， China；
3. Powder Engineering Center， Wuxi Institute of Applied Technology， Tsinghua University， Wuxi 214072， China
Abstract
Objective To address the problem that satellite powder on the surface of gas-atomized iron-based alloy powder leads to a decrease in its flowability and apparent density， which in turn affects the quality of laser cladding layers， this study investigates an effective shaping process for removing satellite powder， and explores the influence mechanisms of satellite powder removal on the physicochemical properties of the powder and the performance of laser cladding layers.
Methods A powder shaping machine was used to treat the iron-based alloy powder with satellite powder on its surface. First， the effects of treatment under air and nitrogen atmospheres on the oxygen content of the powder were compared to determine the protective atmosphere. Subsequently， under a nitrogen atmosphere， different combinations of rotational speeds （3 000， 4 000， 5 000 r/min） and time （10， 20， 30 min） were set to perform shaping treatment on the powder. Scanning electron microscopy （SEM）， X-ray diffraction （XRD）， laser particle size analyzer， and other instruments were used to characterize the morphology， phase structure， apparent density， and flowability of the powder before and after treatment， so as to determine the optimal satellite powder removal process. The powder before and after treatment under the optimal process was used to prepare cladding layers on the surface of 45 steel by coaxial powder feeding laser cladding technology. Metallographic microscopy， a microhardness tester， and an electrochemical workstation were used to compare and analyze the cross-sectional morphology， microhardness， and electrochemical corrosion resistance of the cladding layers prepared from different powders.
Results and Discussion Oxygen content analysis showed that the nitrogen protective atmosphere could effectively control the oxygen increase of the powder. After 30 minutes of treatment， the oxygen mass fraction was close to that of the original powder， meeting the oxygen content requirements for laser cladding powder. XRD analysis showed that none of the treatment processes changed the Fe-Cr-Ni solid solution phase structure of the powder. SEM image analysis revealed that after treatment at rotational speeds of 4 000 r/min and 5 000 r/min for 20 minutes， the satellite powder on the particle surface was effectively removed or flattened， and the particle sphericity was significantly improved. Correspondingly， the apparent density of the powder increased to a maximum of 4.39 g/cm3， and the flowability was also significantly improved. Laser cladding experiments showed that the cladding layer prepared from the powder after satellite powder removal exhibited a smoother surface morphology， greater thickness， higher microhardness， higher self-corrosion potential， and lower self-corrosion current density， demonstrating superior electrochemical corrosion resistance.
Conclusion Under a nitrogen atmosphere， the shaping process with rotational speeds of 4 000 r/min and 5 000 r/min for 20 minutes can effectively remove satellite powder from the surface of iron-based alloy powder. It significantly improves the flowability， apparent density， and sphericity of the powder， without changing the phase structure. The optimization of powder properties leads to more uniform powder feeding and a more stable molten pool during laser cladding， thereby obtaining a cladding layer that is denser， thicker， harder， and has stronger corrosion resistance. This study provides an effective technical approach for improving the quality of iron-based alloy powder for laser cladding and the comprehensive performance of the cladding layer.
Keywords： laser cladding； iron-based alloy powder； gas-atomized powder； satellite powder； particle shaping
Get Citation: Jing Min， Qu Dexin， Tang Zeyang， et al. Removal of satellite powder on surface of iron-based alloy powder and its effect on laser cladding［J］. China Powder Science and Technology， 2026， 32（4）： 1-9.
Received: 2025-12-05, Revised: 2026-05-15, Online: 2026-05-28.
Funding：The research was supported by the National Science and Technology Major Project for R&D and Application of Key New Materials (Grant No. 2025ZD0619900).
DOI：10.13732/j.issn.1008-5548.2026.04.006
CLC No.：TB44
Type Code: A
Serial No.：1008-5548（2026）04-0001-09
