表面技术2025，Vol.54Issue(3)：142-151,10.DOI:10.16490/j.cnki.issn.1001-3660.2025.03.012
送粉量对垂直激光熔覆粉末流场的影响
Effect of Powder Feed Rate on the Powder Flow Field of Vertical Laser Cladding
摘要
Abstract
Laser cladding technology,as an advanced surface modification technology,is characterized by a small heat-affected zone,low dilution rate,and fast repair speed,which has become the main way of repairing and remanufacturing important metal parts.The main research condition for the existing laser cladding powder conveying reveals that the laser cladding head is perpendicular to both the working surface and the horizontal plane.The research on the powder flow field of vertical laser cladding can make up the theoretical gap in the repair of immovable and non-rotatable metal components with tilted and complex surface features and expand the application of metal component repair in additive manufacturing. Firstly,the three-dimensional gas-powder coupling model of four-channel coaxial powder feed for vertical laser melting was constructed to determine the working height of the substrate and the argon gas flow rate of the carrier based on the focus of powder convergence and the distribution of the gas flow field,and then the variation rules of the maximum powder concentration,the diameter of the powder spot and the simulated offset with the amount of powder feed rate were investigated,and finally,a single-pass laser cladding experiment was used to verify the accuracy of the model and predict the cladding morphology. The powder flow field of vertical laser cladding with different powder feed rates was researched,indicating that with the increase of the powder feed rate,the focus of powder convergence did not change significantly,and was at 16 mm from the nozzle.The maximum powder concentration was gradually enhanced from 9.8 kg/m3 to 19.2 kg/m3.The simulated offset progressively increased from 0.23 mm to 0.62 mm.The powder spot diameter slowly increased from 2.8 mm to 3.2 mm at the powder feed voltage of 12 V to 16 V,and sharply increased from 3.2 to 4.3 mm at 16 V to 20 V.The maximum powder concentration,powder spot diameter,and simulated offset were linearly and positively correlated with single-pass laser cladding layer height,layer width,and offset,and the average relative errors between the simulated predictions and the experimental measurements of the cladding layers were 2.15％,1.67％,and 3.05％,respectively. The powder flow field of vertical laser cladding is significantly different from that of conventional laser cladding in which the maximum powder concentration,the simulated offset,and the spot diameter all increase with the increase in powder feed rate.At the same time,the flow field modeling of vertical laser cladding powder is accurate and reliable and enables accurate prediction of the cladding morphology.The research results provide theoretical guidance for the selection and optimization of process parameters in vertical laser cladding.关键词
送粉量/粉末汇聚焦点/最大粉末浓度/粉斑直径/偏移量/模型Key words
powder feed rate/powder convergence focus/maximum powder concentration/diameter of powder spot/offset/model分类
机械制造引用本文复制引用
范红丽,刘玉兵,王治文,张钊,韩日宏,郑明军,齐海波..送粉量对垂直激光熔覆粉末流场的影响[J].表面技术,2025,54(3):142-151,10.基金项目
河北省自然科学基金(E2023210011,E2022210043) Nature Science Foundation of Hebei Province of China(E2023210011,E2022210043) （E2023210011,E2022210043）
