A machining deformation control method of thin-walled part based on enhancing the equivalent bending stiffness

Abstract

In the current study, the experiments are conducted to firstly measure the machining deformation change regulations of two typical thin-walled parts during 1–720 h after machining. Results demonstrate that the deformations of the specimens evidently change in 1–72 h after machining due to the residual stress relaxation. The specimens reach a relatively stable state at 72 h and deformed slowly in 72–720 h. Subsequently, a 3-step machining process was proposed to control the final deformation of two groups of thin-walled specimens. The process was shown as follows: (1) fabricating the workpiece with the extra stiffening ribs in the first-time machining; (2) placing the workpiece freely for 72 h or conducting stress relief process; and (3) machining the reserved stiffening ribs in the second-time machining. Compared with the conventional machining method, the final maximum machining deformations of specimens in group 1 and 2 manufactured by the 3-step machining process are reduced by 29.68% and 48.09%, respectively. Eventually, a machining deformation control method of thin-walled parts based on enhancing the equivalent bending stiffness was summarized and proposed.