不可展曲面功能结构激光刻蚀实验研究

功能性结构在航空航天和卫星通信领域应用十分广泛,对大曲率不可展曲面电磁功能结构的加工是一项十分重大的课题。提出将激光控制软件与导轨运动控制软件进行集成开发,结合分区加工的方法,实现球形不可展曲面电磁功能结构的激光刻蚀。通过将直径100 mm 的304不锈钢半球面划分为2个区域,在2个区域内分别采用3D投影和旋转加工2种不同加工方式,更好地保证了单元结构的加工质量。3D投影应用于切平面夹角β<45°的区域,可以一次性形成激光加工轨迹,省略了分层加工的多次运动,极大地提高了单元加工效率,保证了加工精度。在β>45°区域内采用样件旋转方式,同步调整激光束与球面待加工单元位置,以保证激光束与球面待加工单元法向相重合,减小激光入射角,有效地提高了加工单元的精度。分别利用去除率和样点均方根差评估加工质量,实验结果表明:去除率约为1.00~1.03,样点均方根差约为10~35 μm,整体加工效果显著。

Experimental Study of Laser Etching of Non-Developable Surface Functional Structures

Functional structures are widely used in the field of aerospace and satellite communication,the machining of large curvature non-developable surface ectromagnetic functional structures is still a very important subject. In this paper, the laser control software and the guide rail motion control software are integrated and developed, and the method of zoned machining is combined to achieve laser etching of the electromagnetic functional structure of the spherical shell non-developable surface. The 304 stainless steel hemispherical surface with a diameter of 100 mm is divided into two areas. In the two areas, 3D projection and rotary processing are adopted respectively to better ensure the processing quality of the unit structure. 3D projection is applied to the area with angle β<45°of the cutting plane, which can form the laser machining track at one time, omits the multiple motions of layered machining, greatly improves the unit machining efficiency and ensures the machining accuracy. In the β>45°region, the sample rotation mode is used to adjust the position of the laser beam and the spherical element to be machined synchronously, so as to ensure that the laser beam and the spherical element to be machined coincide with the normal direction, reduce the laser incidence angle, and effectively improve the accuracy of the machining unit. Two quantization parameters, removal rate and root-mean-square difference of sample points, were selected to evaluate the machining quality. The results showed that the removal rate was basically in the range of 1.00~1.03, and the root-mean-square difference of sample points was basically kept in the range of 10~35 μm, and the overall machining effect was remarkable.