Parameter Optimization of Incremental Sheet Metal Forming Based on Taguchi Design and Response Surface Methodology

Author(s):  
Parnika Shrivastava ◽  
J. J. Roy ◽  
M. K. Samal ◽  
P. K. Jain ◽  
Puneet Tandon

Incremental Sheet Forming (ISF) is a flexible and innovative rapid prototyping technique for the fabrication of limited sheet metal components. In the present investigation, the dependency of formability and thickness reduction of ISF parts on tool diameter, incremental step depth along with the preheating of sheet material has been determined. After preheating, initial grain size of the sheet material is selected as a parameter under study. Incremental Sheet Forming process has been studied using Taguchi design of experiments along with Response surface methodology (RSM). ANOVA, 3D surface graphs, S/N ratio and main effect plots have been analyzed. Results indicated that the initial grain size is the most significant parameter as far as forming load and thickness reduction is concerned in ISF. Preheating of the sheet material reduces forming load and favors homogenous thickness distribution. Response surface is optimized and a model developed can be used to predict forming load and thickness reduction within the limits of factors being studied.

Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 661
Author(s):  
Roman Ulrich Christopher Schmitz ◽  
Thomas Bremen ◽  
David Benjamin Bailly ◽  
Gerhard Kurt Peter Hirt

Incremental sheet forming (ISF) is a flexible sheet metal forming process to realize products within short time from design to the first produced part. Although fundamental research on ISF has been carried out around the world, ISF still misses commonly required tolerances for industrial application. In this study, the influences of tool path as well as intrusion depth of the forming tool into the sheet material on the geometrical accuracy were investigated. In the conducted experiments, both flat and stretch-formed sheet metal blanks with different tool paths and intrusion depths were examined. Experimental and numerical investigations showed that changes in the range of a tenth millimeter of the intrusion depth with a consistent tool path lead to different resulting part geometries. A better understanding of the sensitive influence of the tool path and the intrusion depth on the resulting geometry might lead to more accurate parts in the future.


2021 ◽  
Vol 118 (4) ◽  
pp. 401
Author(s):  
Belouettar Karim ◽  
Ould Ouali Mohand ◽  
Zeroudi Nasereddine ◽  
Thibaud Sébastien

New methods in metal forming are rapidly developing and several forming processes are used to optimize manufacturing components and to reduce cost production. Single Point Incremental Forming (SPIF) is a metal sheet forming process used for rapid prototyping applications and small batch production. This work is dedicated to the investigation of the profile geometry and thickness evolution of a truncated pyramid. The influence of process parameters during a SPIF process is also studied. A numerical response surface methodology with a Design of Experiments (DOE) is used to improve the thickness reduction and the effects of the springback. A set of 16 tests are performed by varying four parameters: tool diameter, forming angle, sheet thickness, and tool path. The Gurson-Tvergaard-Needleman (GTN) damage model is used to analyze the damage evolution during material deformation. It is found that the model can effectively predict the geometrical profile and thickness with an error of less than 4%. Furthermore, it is noticed that the forming angle is the most influential parameter on the thickness reduction and springback level. Finally, the damage evolution is demonstrated to be sensitive to the forming angle.


2020 ◽  
Vol 44 (1) ◽  
pp. 148-160
Author(s):  
S. Pratheesh Kumar ◽  
S. Elangovan

Incremental sheet forming is a flexible and versatile process with a promising future in the batch production and prototyping sectors. With decreased design time and negligible production time, incremental sheet forming provides reliability, flexibility, and quality, while being an economical option in contrast to the traditional forming process. In this paper, Inconel 718, a material that has extensive use in aircraft engines, is considered for experimental work to obtain the optimum combination of process parameters. Response surface methodology is used to optimize the process parameters, in particular feed rate, step depth, and lubricant viscosity. The output responses are surface roughness, profile accuracy, and wall thickness. Analysis of variance (ANOVA) is performed using the experimental results to predict the statistical influence of the process parameters. The optimal combination of process parameters is further predicted using a numerical optimization technique to achieve better profile accuracy and surface finish. The results obtained are experimentally validated and are in good agreement with the predicted values.


2007 ◽  
Vol 344 ◽  
pp. 511-518 ◽  
Author(s):  
Markus Bambach ◽  
M. Todorova ◽  
Gerhard Hirt

Asymmetric incremental sheet forming (AISF) is a relatively new manufacturing process for the production of low volumes of sheet metal parts. Forming is accomplished by the CNC controlled movements of a simple ball-headed tool that follows a 3D trajectory to gradually shape the sheet metal blank. Due to the local plastic deformation under the tool, there is almost no draw-in from the flange region to avoid thinning in the forming zone. As a consequence, sheet thinning limits the amount of bearable deformation, and thus the range of possible applications. Much attention has been given to the maximum strains that can be attained in AISF. Several authors have found that the forming limits are considerably higher than those obtained using a Nakazima test and that the forming limit curve is approximately a straight line (mostly having a slope of -1) in the stretching region of the FLD. Based on these findings they conclude that the “conventional” forming limit curves cannot be used for AISF and propose dedicated tests to record forming limit diagrams for AISF. Up to now, there is no standardised test and no evaluation procedure for the determination of FLCs for AISF. In the present paper, we start with an analysis of the range of strain states and strain paths that are covered by the various tests that can be found in the literature. This is accomplished by means of on-line deformation measurements using a stereovision system. From these measurements, necking and fracture limits are derived. It is found that the fracture limits can be described consistently by a straight line with negative slope. The necking limits seem to be highly dependent on the test shapes and forming parameters. It is concluded that standardisation in both testing conditions and the evaluation procedures is necessary, and that a forming limit curve does not seem to be an appropriate tool to predict the feasibility of a given part design.


Sign in / Sign up

Export Citation Format

Share Document