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A stable chip control using inserts with integrated chip formers is difficult, especially if the feed rate or cutting depth is not within the range recommended for the insert. This paper shows the possibility of controlling the chip upcurl radius in turning by using flat inserts without any chip formers. An experimental study was made of the skew cutting of an end of a pipe using a plain water jet with a pressure of up to 80 MPa and a flow of up to 8 l/min. The jet was directed perpendicularly to the cutting edge into the tool/chip interface. Investigations show that the chip upcurl radius can be successfully controlled. A correlation between water jet power, jet momentum and upcurl radius is presented and discussed. An empirical model of the above-mentioned correlation is also suggested.

Development of future aero engine components based on new design strategies utilising topological optimisation and additive manufacturing has in the past years become a reality. This allows for designs that involve geometries of "free form" surfaces and material combinations that could be difficult to machine using conventional milling. Hence, alternative manufacturing routes using non-conventional high energy methods are interesting to explore. In this investigation, the three high energy machining methods abrasive water jet machining (AWJM), electrical discharge machining (EDM) and laser beam machining (LBM) have been compared in terms of surface integrity to the reference, a ball nosed end milled surface. The results showed great influence on the surface integrity from the different machining methods. It was concluded that AWJM resulted in the highest quality regarding surface integrity properties with compressive residual stresses in the surface region and a low surface roughness with texture from the abrasive erosion. Further, it was shown that EDM resulted in shallow tensile residual stresses in the surface and an isotropic surface texture with higher surface roughness. However, even though both methods could be considered as possible alternatives to conventional milling they require post processing. The reason is that the surfaces need to be cleaned from either abrasive medium from AWJM or recast layer from EDM. It was further concluded that LBM should not be considered as an alternative in this case due to the deep detrimental impact from the machining process.

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