Development of optical-heating-assisted incremental forming method for CFRTP sheet - Fundamental forming characteristics in spot-forming -

Abstract

Abstract The aim of this study is to develop an incremental forming method for carbon fiber reinforced thermoplastics (CFRTP) using an optical heating system. The developed forming machine is mainly composed of a vertically articulated robot to control the position of the blank sheet in the X-Y plane, a reciprocating mechanism to generate the reciprocating motion of the forming punch, an electrical cylinder to control the position of the reciprocation mechanism, and a halogen lamp for local heating. A short-fiber CFRTP work sheet of 1.5 mm thickness is used for the experiment. The work sheet is fixed to a blank holder and is locally heated by a halogen lamp set under the work sheet. The heated region of the work sheet is formed by a 2.5 mm radius spherical punch with reciprocating motion, which is located on the opposite side of the halogen lamp. In order to evaluate the fundamental forming characteristics of the developed system, spot forming is performed without feeding a work sheet on the X-Y plane. This study examines the relationship between the pushing distance of the forming punch and the height of the formed point. Forming failure is observed when the forming height exceeds 10 mm. In addition, the shape profile of the formed part follows the shape of the forming punch when the pushing depth does not exceed 7.0 mm.