Prediction of mesoscale deformation in milling micro thin wall based on cantilever boundary

Abstract

The micro channel cold plate is very suitable for the application environment of high heat consumption liquid cooling such as PCB plate and multi-layer components. However, at mesoscale, the titanium alloy micro channel cold plate is micro thin-walled structure of cantilever boundary with weak stiffness, which leads to significant deformation and resultant poor machining accuracy during micro milling. To effectively control and reduce micro thin-walled deformation, a 3D FE cantilever model is established to predict dynamic milling deformation of micro thin wall. The constitutive model of titanium alloy (Ti-6Al-4 V) that includes the strain gradient to consider size effect in micro milling, the edge geometry of milling cutter, the thin-walled microstructure, and micro milling parameters is involved in milling modeling of thin wall. Moreover, a series of micro milling experiments for micro thin wall of titanium alloy at different machining parameters were carried out to investigate the law and mechanism of thin wall deformation in milling micro thin wall subjected to dynamic alternating forces. By comparing numerical and experimental deformation of micro thin wall in micro milling, the accuracy and validity of the prediction model based on cantilever boundary are verified, which provides theoretical support and model basis for the deformation control in milling micro channel cold plate at mesoscale.