Nontraditional finishing processes for internal surfaces and passages: A review

The development of various nontraditional principles to finish the internal surfaces and passages is reviewed. In particular, attention is focused on three relatively mature finishing techniques: abrasive flow machining, internal magnetic abrasive finishing and fluidized bed machining. Their working principles, capabilities and limitations are evaluated accordingly. Finally, the significance of developing internal surface finishing capabilities and the vast potential ahead of this research field are highlighted.