**Adrián Rodríguez, Asier Fernández, Luís Norberto López de Lacalle and Leonardo Sastoque Pinilla \***

Aeronautics Advanced Manufacturing Center, 48170 Zamudio, Spain; Adrian.Rodriguez@ehu.eus (A.R.); Asier.Fernandez@ehu.eus (A.F.); Norberto.lzlacalle@ehu.eus (L.N.L.d.L.)

**\*** Correspondence: cfaa2015@ehu.eus or EdwarLeonardo.Sastoque@ehu.eus; Tel.: +34-688-673-836

Received: 31 October 2018; Accepted: 4 December 2018; Published: 6 December 2018

**Abstract:** Many manufacturing sectors require high surface finishing. After machining operations such as milling or drilling, undesirable burrs or insufficient edge finishing may be generated. For decades, many finishing processes have been on a handmade basis; this fact is accentuated when dealing with complex geometries especially for high value-added parts. In recent years, there has been a tendency towards trying to automate these kinds of processes as far as possible, with repeatability and time/money savings being the main purposes. Based on this idea, the aim of this work was to check new tools and strategies for finishing aeronautical parts, especially critical engine parts made from Inconel 718, a very ductile nickel alloy. Automating the edge finishing of chamfered holes is a complicated but very important goal. In this paper, flexible abrasive tools were used for this purpose. A complete study of different abrasive possibilities was carried out, mainly focusing on roughness analysis and the final edge results obtained.

**Keywords:** flexible abrasive tools; finishing; rounding edge; superalloys
