表面技术2025，Vol.54Issue(12)：145-151,7.DOI:10.16490/j.cnki.issn.1001-3660.2025.12.013
VO2对刀具CVD金刚石涂层热应力的调节作用研究
Regulation of VO2 on Thermal Stress of CVD Diamond Coating on Cutting Tools
摘要
Abstract
This study aims to reduce thermal stress with the thermotropic phase change material(PCM)VO2 as an interlayer,to address the issue of easy detachment of CVD diamond coatings on cutting tools during the cutting process.To investigate the regulating effect of VO2 on the thermal stress of CVD diamond coatings,molecular dynamics simulations are employed.A 3×3×3 supercell model of the M-phase VO2 is established to simulate the phase transition process and calculate the phase transition temperature of the VO2 model.Subsequently,a VO2/diamond layer model is constructed,and the thermal stress within the layer model is calculated over a temperature range of 273.15 K to 523.15 K,yielding a temperature-stress curve for the VO2/diamond layer model.The simulation results indicated that the established VO2 model undergoes a phase transition at approximately 330 K,accompanied by a sudden change in the total system energy and a shift in internal atomic positions.This suggests that the VO2 model undergoes structural changes near the phase transition temperature,demonstrating its thermotropic phase change capability.As the temperature increases,the thermal stress in the VO2/diamond layer model gradually increases.However,near 373.15 K,the system stress abruptly decreases by approximately 400 MPa.Considering that the VO2 supercell model undergoes a phase transition around 330 K,it can be inferred that the sudden stress drop is attributed to the phase transition of VO2.After reaching the phase transition temperature,the atomic positions within VO2 change,leading to a reduction in internal stress.The VO2 films are prepared on YG8 cemented carbide substrates through PVD magnetron sputtering system,followed by the deposition of a CVD diamond coating by HFCVD to form the VO2/diamond coating system.An X-ray stress analyzer is employed to measure the stress changes in the coating system during heating.The experimental results show that at an initial temperature of 303.15 K,the initial stress in the VO2/CVD diamond coating is approximately 600 MPa lower than that of the CVD diamond coating used as a control group.As the system temperature increases,the thermal stress in the VO2/CVD diamond coating system undergoes a sudden change between 323.15 K and 328.15 K,with a stress reduction of approximately 300 MPa.The experimental results regarding the phase transition temperature and stress regulation capability of VO2 are consistent with the simulation trends.The VO2 interlayer can reduce the initial thermal stress of the system and undergo a phase transition during heating,effectively lowering the thermal stress in the CVD diamond coating system,which is significant for enhancing the anti-spalling properties of CVD diamond coatings on cemented carbide cutting tools.关键词
CVD金刚石涂层/VO2/热应力/热致相变材料/调节Key words
CVD diamond coating/VO2/thermal stress/thermotropic PCM/regulation分类
矿业与冶金引用本文复制引用
徐洛,杜星祝,吴超逸,金坚,卢文壮..VO2对刀具CVD金刚石涂层热应力的调节作用研究[J].表面技术,2025,54(12):145-151,7.基金项目
国家自然科学基金(51975287) （51975287）
南京航空航天大学研究生科研与实践创新计划项目(xcxjh20230514)The National Natural Science Foundation of China(51975287) （xcxjh20230514）
Graduate Research and Practice Innovation Program of Nanjing University of Aeronautics and Astronautics(xcxjh20230514) （xcxjh20230514）
