固结磨料小工具头修形抛光钛合金叶片试验研究

Experimental Study of Figuring and Polishing of Titanium Alloy Blades with Fixed Abrasive Tools

为了提高非均匀余量钛合金叶片的表面质量及轮廓精度,提出基于固结磨料小工具技术的钛合金叶片修形与抛光一体化的新方法,根据叶片加工的理论轨迹点与实际测量点之间的空间相对位置关系得到钛合金叶片的加工余量分布情况。基于确定性抛光原理创建叶片表面定量去除模型,在机器人恒力抛光平台上进行钛合金叶片修形抛光试验。试验结果表明:钛合金叶片叶盆的平均粗糙度从起始的0.924μm下降到0.225μm,叶背的平均粗糙度从起始的0.984μm下降到0.249μm,均达到了小于0.4μm的加工要求;叶片表面原有的凹坑和划痕被有效去除,加工后表面没有明显的缺陷,纹理致密均匀;抛光后的叶片轮廓度误差小于叶片所允许的-0.05~0.05 mm误差范围。从而验证了固结磨料小工具头修形抛光非均匀余量钛合金叶片的可行性,为航空发动机叶片的修形与抛光的工艺选择提供了参考依据。

To improve the surface quality and profile accuracy of non-uniform allowance titanium alloy blades,a new method of integrating the figuring and polishing of titanium alloy blades was proposed based on fixed abrasive tool technology.The distribution of machining allowances of titanium alloy blades was obtained according to spatial relative position relationship among the theoretical trajectory points and the actual measurement points of processing blades.The principle of deterministic polishing was used to establish the quantitative removal model of blade surfaces.The figuring and polishing of titanium alloy blade experiments were carried out on robot constant force polishing platform.Experimental results show that the average roughness of titanium blade basin decreases from 0.924μm to 0.225μm,and the average roughness of blade back decreases from 0.984μm to 0.249μm.Both of which meet the processing requirements of less than 0.4μm.The original pits and scratches on the blade surfaces are effectively removed.There are no obvious defects on the machined surfaces and the texture is dense and uniform.The profile errors of the polished blades are less than the allowed range of-0.05~0.05 mm for the blades.The feasibility of the figuring and polishing of titanium alloy blades with non-uniform allowance of the fixed abrasive tool is verified,which provides a reference basis for the processing selection of figuring and polishing of aero-engine blades.