Machining of a film-cooling hole in a single-crystal superalloy by high-speed electrochemical discharge drilling
Machining of a film-cooling hole in a single-crystal superalloy by high-speed electrochemical discharge drilling
复制标题
高速电化学放电钻孔单晶高温合金气膜冷却孔加工
DOI：
10.1016/j.cja.2015.06.021
复制
发表时间：
2016-04-01
影响因子：
5.7
通讯作者：
Zhu Di
中科院分区：
文献类型：
--
作者：
Zhang Yan;Xu Zhengyang;Zhu Di
单晶高温合金是制造航空发动机涡轮叶片的典型先进材料。它们具有高硬度和高强度的独特特性，这使得它们极难加工。然而，涡轮叶片的一个关键结构，即气膜冷却孔，需要在单晶高温合金中进行加工；这种加工具有挑战性，特别是考虑到航空发动机工业对加工效率和质量的要求越来越高。管电极高速电火花钻削(TSECDD)是一种高速电火花钻削与电化学加工相结合的复合加工技术，具有加工效率高、加工精度高、无需重铸层等优点。在本研究中，TSECDD被用于加工镍基单晶高温合金(DD6)中的气膜冷却孔。采用田口实验法对加工参数进行了优化。实验结果表明，TSECDD能有效地钻取气膜冷却孔，最佳工艺参数为：脉冲宽度12 mU S，脉冲间隔30 mU S，峰值电流6A，盐溶液电导率3ms/cm。最后，用TSECDD加工了一个孔，并与电火花加工的结果进行了比较。TSECDD在改善表面质量和消除重铸层方面具有很好的应用前景。(C)2015年提交人。爱思唯尔有限公司代表CSAA&BUAA制作和主办。
Single-crystal superalloys are typical advanced materials used for manufacturing aeroengine turbine blades. Their unique characteristics of high hardness and strength make them exceedingly difficult to machine. However, a key structure of a turbine blade, the film-cooling hole, needs to be machined in a single-crystal superalloy; such machining is challenging, especially considering the increasing levels of machining efficiency and quality demanded by the aeroengine industry. Tube electrode high-speed electrochemical discharge drilling (TSECDD), a hybrid technique of high-speed electrical discharge drilling and electrochemical machining, provides high machining efficiency and accuracy, as well as eliminating the recast layer. In this study, TSECDD is used to machine a film-cooling hole in a nickel-based single-crystal superalloy (DD6). The Taguchi methods of experiment are used to optimise the machining parameters. Experimental results show that TSECDD can effectively drill the film-cooling hole; the optimum parameters that give the best performance are as follows: pulse duration: 12 mu s, pulse interval: 30 mu s, peak current: 6 A, and salt solution conductivity: 3 mS/cm. Finally, a hole is machined by TSECDD, and the results are compared with those obtained by electrical discharge machining. TSECDD is found to be promising for improving the surface quality and eliminating the recast layer. (C) 2015 The Authors. Production and hosting by Elsevier Ltd. on behalf of CSAA & BUAA.