Reduction of material swelling and recovery of titanium alloys in diamond cutting by magnetic field assistance

Ultra precision machining (UPM) is extensively used to fabricate high accuracy products. However, the problematic material swelling/recovery effect due to the elastic recovery of materials in UPM remains unresolved. It causes a ragged surface and extra engineering tolerances which are unadoptable in extremely precise components. In particular to high elastic recovery rate with low thermal conductivity materials like titanium alloys, the swelling effect is intensified during machining processes. In this study, a magnetic field was superimposed on titanium alloys during the single point diamond cutting which aimed to minimize the material swelling effect on the machined surface using the magnetic field influence. In the experiments, titanium alloys were located at the center of two permanent magnets with intensity 0.02T and undergone a diamond groove cutting. The experimental results showed the material swelling/recovery on the machined surface was significantly reduced in presence of magnetic field in comparison to that of diamond cutting without a magnetic assistance; the accuracy of depth of cut, width and radius of cutting groove in a magnetic field reached satisfactorily over 98%. The proposed machining technology solves the problem of material swelling/spingback of low thermal conductivity materials by a cost-efficient way which is needless of complicated equipment. (C) 2017 Elsevier B.V. All rights reserved.