점진적 롤 성형공정을 이용한 이중곡률의 금속판재 제작 및 정밀 성형을 위한 형상 예측Manufacture of Doubly Curved Sheet Metals Using the Incremental Roll Forming Process and Prediction of Formed Shapes for Precision Forming
A flexible incremental roll forming process has been developed by adopting the advantages of the incremental forming process and the roll forming process: i.e., inherent flexibility of the incremental forming process and continuous bending deformation of the roll forming process. It has an adjustable roll set as a forming tool composed of one upper center roll and two pairs of lower support rolls, which plays a key role during forming process. Through the experiments based on the various combinations of process parameters, it is shown that the incremental roll forming process is so effective as to manufacture various doubly curved sheet metals including concave-convex combination shapes in which there exists a line of inflection. The proposed relationship of the experimental parameters and the radius of curvature of the formed sheet boundary is found to be useful in prediction and control of the final shape.