Tool Wear Finite Element Analysis And Tool Life Prediction In Stainless Steel Milling

Stainless steel is widely used in aerospace, shipping manufacturing, petroleum and chemical industry and many other fields. However, stainless steel is a typical material which is difficult to machine. During the machining process, the tool is easy to wear, which will not only reduce tool life greatly but also affect the cutting stability, machining accuracy and efficiency. Therefore, researches on tool wear and tool life prediction when machining stainless steel is of great guiding significance and application value.A coupled thermal-mechanical model is established with ABAQUS software taking consideration of characteristics of milling stainless steel. Material constitutive model, friction and heat transfer on the interface as well as chip separation criteria in metal cutting simulation are studied. As for large strain and large strain rate phenomenon during the simulation, Johnson-Cook material model and shear failure criteria are adopted.Machining process and heat transfer process are simulated and analyzed. Normal pressure, temperature of tool surface and relative sliding velocity between tool and workpiece are obtained through the above finite element analysis. Then nodal displacement of tool surface is calculated using Usui tool wear rate model, and tool geometry is updated accordingly. A tool life prediction model is derived based on multiple linear regression theory, and parameters of the model are attained according to the tool wear date from the simulation.Finally, the prediction results are compared with actual tool wear during the milling of liquid rocket engine nozzle cooling channels, and reasons for the discrepancy are discussed. The comparison result indicates that the tool life prediction model established in this thesis is of certain reference value and guiding significance for the machining of nozzle straight grooves.