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目的给出车刀在切削过程中破损的声发射源和声发射信号的时域数学模型．方法利用广义虎克定律，建立了车刀刀片裂纹扩展时的声发射能量模型，根据能量守恒原则，利用时频变换理论的帕什瓦定理推导出车刀破损的声发射信号时域数学模型．结果建立了车刀破损的声发射数学模型，阐明了车刀破损时影响声发射信号特性的各种因素及其相互关系．结论为有效地利用声发射方法检测车刀裂纹和断裂提供了可靠的理论基础．
Aim To provide a time-domain mathematic model of acoustic emission source and acoustic emission signal of turning tool damaged during cutting. Methods Based on the generalized Hooke ’s law, the acoustic emission energy model of the tool insert during crack propagation is established. According to the principle of conservation of energy, the time domain mathematical model of the acoustic emission signal of the tool breakage is deduced by the Pashvah theorem of time - frequency transformation theory. Results A mathematical model of acoustic emission of turning damage was established, and the various factors affecting the characteristics of acoustic emission signals and their relations were expounded. Conclusion The study provides a sound theoretical basis for effectively detecting the flaw and fracture of the turning tool by acoustic emission.