Finite element simulation study on internal milling deformation of weak stiffness crank structures

In this paper, the influence of surface residual stress on machining deformation in crankshaft internal milling is investigated through finite element simulation, and the internal milling process parameters are optimized with the objectives of low stress and minimal deformation. The axial maximum residual stress at the cylindrical surface of the crank pin exhibits the most significant impact on deformation. The optimal internal milling parameters are determined as: tool disc rotation speed 80 r.min-1, cutting depth 0.24 mm, and workpiece rotation speed 5 r.min- 1. Under these conditions, the axial maximum residual stress at the cylindrical surface reaches -338 MPa with minimized deformation.