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Indexed by:期刊论文

Date of Publication:2016-05-01

Journal:INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:84

Issue:5-8

Page Number:1725-1735

ISSN No.:0268-3768

Key Words:Abrasive flow machining; Blisk; Numerical simulation; Surface finish uniformity

Abstract:The blade surface roughness of blisk is of significance to performance of aero-engine on the aspects of thrust weight ratio and service life, etc. However, it is difficult to achieve uniform surface finish because of the strong geometry interferences arising from the complex structures, through the processes of manual finishing, belt grinding, and CNC polishing. In this paper, abrasive flow machining (AFM) process is adopted to polish blade surfaces of blisk with the aimto acquire qualified uniform surface finish, by virtue of AFM's excellent machining flexibility for parts with structures difficult to machine. Researches on surface finishing are taken for the proposed experimental prototype blisk with straight blades, through the approaches of both experiments and numerical simulations, where abrasive media with different mesh sizes and mass fractions are used. Experimental results show that surface roughness values near regions of leading/trailing edges are higher than those in regions of blades' center, although surface roughness of the whole blades is improved obviously after AFM process. And, results from numerical simulations indicate that there exist irregular flows of abrasive media and high-pressure gradients near the leading/trailing edges, which provides reasonable explanations why uneven surface finish of blades is not achieved. Based on these analyses, a new fixture with guild blocks is proposed and proper fixture parameters are set to efficiently regulate the abrasive media flows near leading/trailing edges, and the validation experiments show that surface finish uniformity of blades is achieved with this apparatus. The conclusion could be drawn from the studies of this paper that uniform surface finish for blisk is achievable through properly designed AFM fixtures.