金刚石与磨料磨具工程2025，Vol.45Issue(6)：786-793,8.DOI:10.13394/j.cnki.jgszz.2024.0104
金刚石拉丝模中金刚石涂层的制备工艺及性能
Preparation process and properties of diamond coating in diamond drawing die
摘要
Abstract
Objectives:To improve the drawing efficiency and service life of diamond wire drawing die,this study pre-pares high-performance diamond coatings on the surface of the bore of cemented carbide molds by hot filament chemic-al vapor deposition(HFCVD)technology.The research work focuses on the problems of easy peeling of the diamond coating and surface roughness after wire drawing in industrial applications,optimizes the deposition process to improve the adhesion strength and surface finish quality,and explores the failure mechanism of the coating in depth.The study includes the effect of deposition temperature on the microstructure of the coating and the analysis of coating damage and failure mechanisms.Methods:In this study,indigenously designed HFCVD equipment(reaction chamber diameter 680 mm,total power 35 kW)is used for the experiments.A YG6 cemented carbide drawing die(outer diameter 16 mm,height 13 mm,diameter of inner bore sizing zone 2.6 mm)is used as the substrate.The substrate is chemically pre-treated in steps before deposition:first,it is treated with an alkaline solution of K3[Fe(CN)6]:KOH:H2O=1:1:10 for 10 min,followed by etching for 20 s using an acidic solution of HCl:H2O2=1:4 to enhance the coating bonding and nucleation quality.The diamond coatings are deposited using tantalum filaments threaded through a cemented carbide substrate at 900 and 950℃,respectively,to systematically compare the formation patterns of nano-and micron dia-mond coatings at the two temperatures.The composite coating process is further used to deposit the micrometer dia-mond base layer first,followed by the in situ deposition of the nanodiamond surface layer.The temperature field distri-bution inside the wire drawing die is analyzed by finite element simulation,the coating morphology is observed by scan-ning electron microscopy,the diamond quality and non-diamond phase content are detected by Raman spectroscopy,the composition of the physical phases is analyzed by XRD,and the geometric undulation of the surface is quantified by laser confocal microscopy.Results:Temperature has a regulatory effect on the coating structure.Under 950℃,the dif-fusion ability of high concentration of carbon active groups is enhanced,and nano-diamond coatings are formed by de-position in the compression and sizing zones;while under 900℃,micron diamond coatings are mainly formed in the same area.The differences in failure mechanisms were analyzed.The nano-diamond coatings exhibited large delamina-tion and shedding due to insufficient interfacial bonding;the micron diamond coatings formed steps in the transition zone between the compression zone and the sizing zone due to polishing difficulties in actual application,which triggered intense friction during drawing,leading to deep groove-like wear on the coating surfaces and causing scratches on the wire surfaces.The composite coating has better performance,with a strong interfacial bond provided by the mi-cron diamond base layer and a surface roughness of<50 nm after polishing of the nanodiamond surface layer,and the actual application of the drawing test shows that the wire drawing distance of the composite coating drawing die is up to 100 km,which is a significant improvement compared with the drawing distance of the single nano-diamond coating(50 km)and the micron diamond coating(15 km).Conclusion:In this study,it is found that the deposition temperature(900-950℃)can regulate the diffusion depth of carbon reactive groups,which dominates the microstructural evolution of the diamond coatings,with high temperature promoting the formation of nano-diamonds and low temperature facilit-ating the growth of micron diamonds.The micron/nano-composite coating design effectively synergizes the advantages of high bonding strength of the bottom layer and low roughness of the surface layer,and enables the drawing distance of the wire drawing die to be increased to 100 km.This process provides a reliable technical route to reduce the consump-tion of tungsten resources,and promotes the large-scale industrial application of high-performance diamond-coated wire drawing dies.Future research is needed to further optimize the deposition time of the micron and nano layers in order to improve the service life of the wire drawing die and reduce the production cost.关键词
金刚石/拉丝模/有限元模拟/失效机理Key words
diamond/drawing die/finite element simulation/failure mechanism分类
通用工业技术引用本文复制引用
许光宇,李自超,李鸿,刘峰斌,李成明,安康,吴海平,张永康,李利军,张亚琛,任美玲,王梦鑫,肖娜薇..金刚石拉丝模中金刚石涂层的制备工艺及性能[J].金刚石与磨料磨具工程,2025,45(6):786-793,8.基金项目
国家自然科学基金(52102034) （52102034）
国家自然科学基金区域联合基金项目(U23A2025) （U23A2025）
北京市教育委员会科学研究计划项目(KM202410009010) （KM202410009010）
北方工业大学有组织科研(2023YZZKY12) （2023YZZKY12）
北方工业大学研究生教育教学改革研究项目(YJS2024JG16). （YJS2024JG16）
