Many sheet forming processes such [sic] hammering and spinning, have been used in the manufacturing industry for decades and consequently have strengths and weakness that are well known. In contrast, Incremental Sheet Forming (ISF) is an emerging type of forming process whose capabilities are not yet fully understood. So while it is clear that ISF processes have several advantages, such as low cost and good surface finish [sic]. It has proved difficult to define the limits of the process in terms of macro-parameters such as deformation and sheet thickness. So whereas the capabilities of many sheet metal manufacturing processes are effectively characterized by forming limit curves this has not been possible with ISF. In other words, there is a lack of methodologies for assessing the feasibility of using ISF for particular components. This thesis investigates several aspects of the ISF process and develops a quantitative methodology that allows a first approximation of the feasibility of component manufacturing using the ISF process in terms of deflection and thickness reduction. It was found that thickness reduction can be accurately modeled in terms of analytical model developed for sheet metal forming. The predictions of the method are assessed and found to give a good correspondence with measured data for the range of wall angles, materials and geometries assessed. The parameters of the proposed methodology have been determined by experimental studies of commercially pure Titanium Grade 4 (CpTi), Aluminium alloys (AA1050-H-14, AA2024-O and AA7075-O) and Stainless Steel (SS304-L) to understand the process of incremental sheet forming and its impact on the final properties of the sheet metal. The proposed method called "ISF-FCheck" uses two charts to quantify maximum strain in relation to the depth and thickness reduction. Discussion of these results has also supported the development of a more detailed understanding of the interaction of the process parameters and lead to a new theoretical and graphical representation of the ISF process.
|Date of Award||17 Feb 2017|
- University Of Strathclyde
|Sponsors||University of Strathclyde & EPSRC (Engineering and Physical Sciences Research Council)|
|Supervisor||Jonathan Corney (Supervisor) & Andrzej Rosochowski (Supervisor)|