Ceramic cores determine the moulding accuracy of a turbine blade’s cavity, which strongly affects thermal diffusion performance and the service life of a turbine engine. To get a high quality ceramic core after the preliminary process, this paper deals with a laser trimming technology for ceramic casting cores via double picosecond laser scanning for the first time. Instead, the core ceramic foils were firstly machined at a combination of different laser processing parameters to determine the necessary laser trimming technology. Three different laser pulse duration regimes including femto-, pico- and nanosecond were examined and picosecond laser was selected for trimming of the core considering a serious recast layer occurrence in nanosecond laser processing and large amounts of faintly bonded aerosols on the side-wall of the machined surface in femtosecond laser processing. The removal profiles of the machined ceramic foils were characterized in terms of depth, deviation of lin...

中文翻译：

---

通过双皮秒激光扫描对涡轮机叶片的氧化铝基陶瓷铸芯进行修整

陶瓷芯决定涡轮叶片腔体的成型精度，这会严重影响涡轮机的热扩散性能和使用寿命。为了在初步处理后获得高质量的陶瓷芯，本文首次通过双皮秒激光扫描技术处理了用于陶瓷铸芯的激光修整技术。取而代之的是，首先在不同的激光加工参数的组合下加工芯陶瓷箔，以确定必要的激光修整技术。三种不同的激光脉冲持续时间方案，包括飞秒，考虑到皮秒级和纳秒级，并考虑了皮秒级激光的修整，考虑到纳秒级激光加工中严重的重铸层出现以及飞秒级激光加工中加工表面侧壁上大量微弱结合的气溶胶。加工后的陶瓷箔的去除轮廓通过深度，线性偏差来表征。