| With the continuous development of science and technology and the needs of industrial production,deep micro-hole has a wide range of applications in the fields of aerospace,weapons,medical devices and automotive.Especially for the processing of deep micro-hole with thermal barrier coating gas film cooling hole,the common electrolytic processing can not process non-conductive ceramic materials,laser processing micro-hole with recast layer and micro-cracking,and processing high-quality deep micro-hole requirements of the laser equipment is too high.The combined laser-electrolytic processing technology for deep micro-hole processing of nickel-based alloys with thermal barrier coating is carried out.The main research of this paper is as follows.First,a new method of laser electrolytic combined processing of deep micro-hole with thermal barrier coating material is proposed.For the micro-hole processing of thermal barrier coating,UV nanosecond pulsed laser spin-cutting processing of ceramic coating,and electrolytic microfabrication at the same processing position of the workpiece to etch out the recast layer produced during laser processing of micro-hole and deep micro-hole processing of high temperature alloy.Secondly,the theoretical basis of the process mechanism of laser-material interaction and electrolytic etching of metallic materials is studied,and the experimental scheme of combined laser-electrolysis processing is determined on the built laser-electrolysis microfabrication platform.The orthogonal tests of laser micro-hole processing of ceramic coating and electrolytic processing of deep micro-hole of high temperature alloy with thermal barrier coating are conducted separately.Finally,for micro-hole processing of non-conductive ceramic materials,the comparative analysis and optimization of the influence of processing parameters on the evaluation criteria of laser processing micro-hole entrance roundness and lateral clearance are carried out by using nanosecond UV laser photo-thermal action spin-cutting processing.For the deep micro-hole processing of high-temperature alloys coated with thermal barrier coating,the deep micro-hole processing of high-temperature alloys is performed by electrolytic processing at the same processing position of the workpiece with ceramic coated micro-hole processed by laser rotary cutting.The feasibility of combined processing of deep micro-hole with thermal barrier coating was verified.The optimized combined laser electrolytic machining parameters were selected for the test to verify that the hole exit and entrance roundness,side clearance(machining accuracy±0.05mm)and taper etc,meet the machining requirements. |
