Percussion Drilling of Deep Holes Using Picosecond Ultrashort Pulse Laser in Ni-Based Superalloy Coated with Ceramic Thermal Barrier Coatings

Good heat dissipation performance of aero-engine an effectively improve the service performance and service life of aero-engine. Therefore, this paper studies the machining method of cooling holes of high-temperature existent material GH 4169 for aero-engine innovatively puts forward the mask electrochemical machining method of cooling holes and explores the entrance morphology and taper formation law of the hole structure of high-temperature resistant material GH 4169. The mathematical model of anode dissolution of cooling holes in ECM is established, and the influence of voltage and electrolyte flow rate on cooling holes in ECM is analyzed. Compared with the mask-less electrochemical machining, the inlet radius of cooling holes in mask electrochemical machining is reduced by about 16.0% and the taper is reduced by 52.8% under the same machining parameters, which indicates that the electrochemical machining efficiency of mask is higher and the machining accuracy is better. Experiments show that the diameter of the mask structure improves the accuracy of the inlet profile of the cooling hole in the ECM. The diameter of the mask increases from 2 mm to 2.8 mm, and the inlet radius of the cooling hole increased from 1.257 mm to 1.451 mm When the diameter of the mask is 2.2 mm, the taper of the cooling hole decreased by 53.4%. The improvement effect is best, and the thickness of the mask has little influence on the forming accuracy of the cooling hole.

Section: Mathematical Model Of Anodic Dissolution In Electrochemical ...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Simulation Analysis and Process Evaluation of Cooling Hole Forming Precision in Mask Assisted Electrochemical Machining Based on GH4169

Dai

2022

“…Liu et al [11] explored the impact of laser pulse parameters, threshold, and wavelength on the hole size using picosecond ultrashort pulse laser drilling. Their findings indicated that a laser with a wavelength of 1064 nm was required to drill holes larger than 100 µm in diameter.…”

Section: Introductionmentioning

confidence: 99%

Investigation on Thermal Barrier Coating Damages for Ultrafast Laser Drilling of Cooling Holes

Wang,

Hu,

Zuo

et al. 2023

To mitigate the challenges pertaining to coating damage and processing defects arising from the utilization of ultrafast laser drilling for microhole creation in thermal barrier coatings (TBCs), thereby exerting substantial influence on the long-term durability of these microholes, the investigation proposes a comprehensive methodology. It encompasses the design of a two-factor four-level full factorial experiment and the execution of experimental research on picosecond laser drilling of TBC microholes. By meticulously analyzing the morphology of the microholes and the coating interface, the damage mechanisms associated with picosecond laser drilling of TBC microholes, as well as the influence of laser process parameters on coating damage, are revealed. The findings reveal that the optimal microhole entrance quality and the lowest roughness along the hole perimeter are attained at a laser power of 12 W and a scanning speed of 320 mm/s. Moreover, at a laser power of 30 W and a scanning speed of 320 mm/s, the minimal crack length on the blunt angle side of the hole and the highest machining quality are observed.

“…Comparatively, laser drilling with high peak energy is among the best hole machining methods for ceramics substrates. Liu et al and Zhao et al summarized that the advantages for laser drilling are non-contact processing, lack of tool loss, high efficiency and precision, among others [ 3 , 4 ].…”

Section: Introductionmentioning

confidence: 99%

Optimization of Trepanning Patterns for Holes Ablated Using Nanosecond Pulse Laser in Al2O3 Ceramics Substrate

Zhao

Mei

2021

Self Cite

Trepanning pattern is an important factor in laser hole machining, affecting both the hole quality and process efficiency. The influence of laser trepanning patterns on the hole ablating using nanosecond pulse laser in Al2O3 ceramics substrate was studied. Two laser trepanning patterns were evaluated, filled spiral trepanning and multiple rings trepanning, with the optimized laser machining parameters. In conjunction with the studies, the hole saturated taper and the saturated processing time were taken as the primary criteria for evaluation of the hole quality and the machining efficiency, respectively. Finally, the trepanning patterns were optimized aiming for the high hole quality; the process was based on the saturated hole tapers. The hole high qualities and machining efficiencies were obtained based on the saturated processing time, which was proven to have a great significance when using the nanosecond pulse laser to machine Al2O3 ceramics substrate.