Temperature Analysis for the Tool-Sheet Interface

in Single Point Incremental Forming (SPIF)

Tao He a, Xin Zhang a, Dohyun Leem a, Huaqing Ren a, Newell Moser a

Hirotaka Miwa b, Toshikazu Nanbu b, Murakami Ryou b, Jian Cao a, and Qian Wang a

a Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA

b Nissan Research Center, Nissan Motor Co., Ltd., Kanagawa, Japan

Abstract
Single point incremental forming (SPIF) is a highly versatile and flexible process for rapid manufacturing of complex sheet metal parts, in which a tool moves along a predefined path and forms the sheet to its desired shape. The forming process involves significant temperature rise if the tool speed is high, and the current work is focused on the analysis of heat transfer problem at the tool-sheet interface subjected to friction and sheet plastic deformation. A global-local Finite element method (FEM) is used to determine the deformation-induced heat source in a forming process, while the frictional heat source is obtained through solving a contact problem. Frequency response functions (FRFs) for temperature rise are analytically derived and then converted into influence coefficients (ICs); the conjugate gradient method (CGM) and the fast Fourier transform (FFT) are utilized to accelerate the numerical calculation. The proposed model is implemented to analyze the heat partition between the tool and the sheet and temperature rise at the tool surface under different forming conditions.