Visual Categorization and Quantification of the Orange Peel Effect in Single Point Incremental Forming at High Forming Speeds

In recent years, studies into dieless formed sheet surface features, internal roughness due to direct tool contact, and external roughness from indirect contact have been numerous. Much focus has been given to the internal surface finish of SPIF parts, particularly on how to better control the finish by changing forming parameters. Studies by Ham have shown the internal roughness is affected primarily by the tool and step sizes (Ham 2009). Other factors such as material thickness and type as well as forming angle, rotational speed and feed speed may have some contribution to both the internal and external roughness. This paper focuses on the external surface finish particularly in understanding how forming parameters influence roughness through formation of 'orange peel.' Published in the Transactions of NAMRI/SME, Vol. 38, 2010, pp. 679-686.