聚晶立方氮化硼脉冲激光烧蚀传热与去除规律OA

A temperature-dependent equivalent thermophysical property model was first developed.It was based on constituent volume-fraction mixing and the Voigt-Reuss-Hill scheme.Then,a transient heat-transfer model was established.It considered Gaussian spatial distribution,multi-pulse temporal modula-tion,and scanning dwell behavior.Two computational cases were defined.They described peak tempera-ture rise and heat accumulation,respectively.An Arrhenius-integral-based removal criterion was further introduced.A two-stage calibration strategy was adopted.It combined low-power kinetic anchoring with high-power correction.This strategy was used to predict ablation dimensions.Experimental validation was performed under two representative conditions,namely 1-pass and 7-pass ablation.The PcBN surface temperature showed a periodic response.Rapid heating and slow cooling were observed.Clear inter-pulse heat accumulation was found.After high-temperature physical correction,the model suppressed the non-physical overestimation of surface peak temperature at high power.The R² values of depth prediction were 0.906 and 0.708 for single-pass and seven-pass ablation,respectively.The model also described the varia-tion trend of cross-sectional area well.Cross-sectional SEM results showed a more obvious remelted and redeposited layer near the groove surface at high power.A more pronounced heat-affected zone was also observed.These features were important sources of the measured width deviation.The proposed model can describe the transient thermal response and material removal behavior during multi-pulse nanosecond laser ablation of PcBN.It provides a theoretical basis for thermal-effect analysis and process optimization in PcBN laser machining.A coupled model was established for transient heat transfer and material removal in polycrystalline cubic boron nitride(PcBN).It addresses rapid transient heating,strong heat accumula-tion,and difficult prediction of ablation dimensions during multi-pulse nanosecond laser ablation.