Study on the surface roughness of the spun parts produced by the textured and non-textured forming tool

The paper brings the results of an experimental study of the multi-pass cold metal spinning process employing a laser-textured tool of 90MnCrV8 (1.2842) steel. The tool with a nose radius surface modified by pulse laser machined hexagonally arranged texture made up of dimple-like depressions with a diameter of 100 μm, depth of 20 μm, and density of 6 % was applied for testing the surface finish of DC01 low carbon steel sheet of the thickness 1 mm by applying various spinning tool pass profiles, mandrel speeds, and tool feeds. On the cylindrical-shaped spun samples, the surface roughness of the spun cup wall was evaluated. The measurements in 0°, 45°, and 90° directions related to the blank material rolling direction were realised, and these responses were compared with those which have been observed on the parts produced by the conventional, non-textured tool. The analysis showed that applying a laser-textured roller reduces the arithmetic mean height of the spun part roughness profile Ra by about 30 % compared to this achieved using the non-textured roller. The Ra reduction of about 15.2 % compared to the initial roughness of the blank material was documented. In contrast, the influence of the planar anisotropy of the material on the surface roughness was not proven.