Scope and Objectives

To develop
1. A dieless forming process with adaptive and dynamic support
2. Use of ultrasonic vibration to enhance formability
3. Strategies to produce components of uniform thickness, desired geometric accuracy, surface finish and mechanical properties
4. CAD/CAM/CAE suite based on process mechanics, for pre-fabrication simulation
5. An indigenous machine tool for implementation

Deliverables

1. Technology for AdDSIF process
2. Ultrasonic vibration assisted AdDSIF process Integrated CAD/CAM/CAE tools
3. Novel adaptive dieless forming setup for validation
4. Process knowledge
5. Forming strategies for limited batch and critical geometry components
6. AdDSIF machine tool
7. IPR on AdDSIF process and Ultrasonic vibration assisted AdDSIF process
8. IPR on AdDSIF machine

Videos

Scientific Output

Incremental Sheet Forming (ISF) is a dieless sheet metal forming technique. In ISF, a forming tool mounted on a CNC milling centre follows the predefined incremental tool path and deforms the sheet, which is clamped at its outer periphery. The induced stresses due to forming tool results into local plastic deformation of sheet and the outcome is desired 3D geometry. Although, being flexible and low cost solution, SPISF is also marred with several process constraints and limitations like geometric inaccuracy, non-uniform thickness distribution and limited control over mechanical characteristics of the formed components. To overcome some of these drawbacks, Double Sided Incremental Forming (DSIF) was introduced. DSIF is a variant of general ISF process which uses two tools on either side of the sheet metal follows a predefined path to form a desired component by squeezing and bending. The sheet gets sandwiched between the tools at the deformation zone. One of the tools is used to indent the sheet and the other tool is used to support (or squeeze) the sheet. By employing two forming tools at each side of the sheet, the DSIF process can provide additional process flexibility. By providing controlled ultrasonic vibration to the forming tool, quality of process can be further improved and better results are expected. Use of ultrasonic vibration to the forming tool would cause an alternating motion at the tool-sheet interface in the local deformation zone. Thus, material flow and surface quality of the formed part would improve. Besides, forming can be performed at higher feed rates. However, when it comes to hard to form metals, the formability of the material limits the applicability of ISF. Elevated Temperature ISF (ET-ISF) is a potential solutions to incrementally form the parts which otherwise are difficult to form. In ET-ISF, sheets are heated by external source to a specific temperature and then incrementally formed in that condition. Due to heating, yield strength of material reduces which enhance its formability. Hence, ET-ISF technique is very helpful in efficiently forming several materials which are widely used in the field of automobile, aerospace and biomedical. In the present work, Adaptive Double Sided Incremental Forming (AdDSIF) strategies are coupled with Ultrasonic Vibration-assisted ISF (UVaISF) to enhance the process capabilities. With AdDSIF, the double-sided tool path adapts to different geometrical attributes of a given component and facilitates forming with improved structural accuracy, surface finish and process formability. Moreover, UVaISF improves material characteristics by influencing microstructural phenomena of deformation. The work couples AdDSIF and UVaISF to facilitate forming of complex shapes from metal sheets with better part quality. The methodology would provide a geometry independent solution. Suitable CAD/CAM/CAE tools based on process mechanics are developed to implement the desired shape forming strategies. Besides, a novel and one of a kind machine tool setup is designed and developed to realize the proposed solution. In order to further improve the effect of UVaISF, the process is further coupled with ET-ISF by supplying heat to the while it is still being deformed with a UVaISF.

Results and outcome till date

1. Vibration induced Incremental Sheet Forming tool paths strategy was developed and implemented
2. Thermo graphical study and numerical simulation of Vibration induced Incremental Sheet Forming was performed along with experimental validations
3. Ultrasonic Vibration assisted Incremental Sheet Forming (UVaISF) tool was designed and tested with numerical analysis
4. UVaISF strategies have been developed and are being tested with Finite Element Analysis (FEA) simulations
5. An experimental setup/machine for Adaptive Double Sided Incremental Forming (AdDSIF) was designed and is presently being fabricated
6. Tilt axis for Adaptive Double Sided Incremental Forming setup was designed and is presently being fabricated
7. An experimental setup/spindle for UVaISF was designed and is presently being fabricated
8. Double sided Incremental Forming (DSIF) strategies have been developed and are being tested with Finite Element Analysis (FEA) simulations
9. A damage model for predicting damage and fracture in parts to be formed by AdDSIF process has been developed
10. Johnson-Cook model for efficient simulation of of ISF, DSIF, AdDSIF and UVaISF processes through FEA models have been developed and implemented
11. Mechanical test specimen for parameter acquisition under complex were designed and developed for facilitating efficient simulation of ISF, DSIF, AdDSIF and UVaISF processes
12. A VUMAT subroutine of material model for effective simulation of ISF, DSIF, AdDSIF and UVaISF is developed in-house
13. Material Benchmarking of various materials to be formed with ISF, DSIF, AdDSIF and UVaISF processes is in progress
14. A Computer Aided Manufacturing (CAM) tool for generating tool paths for DSIF has been developed
15. A CAM tool for generating tool paths from geometries containing multiple features is being developed
16. Experimental setup for UVaISF at elevated temperatures has been developed
17. UVaISF with elevated temperatures strategies have been developed and are being tested with Finite Element Analysis (FEA) simulations
18. Python drivers to implement Adaptive paradigm in Computer Numerical Control (CNC) control system are developed
19. A Knowledge based system for facilitating efficient implementation of ISF, DSIF, AdDSIF and UVaISF processes is being developed
20. Development of CAD/CAM/CAE module is in progress 21. Reverse Engineering Setup for part validation has been developed and established

Societal benefit and impact anticipated

Metal forming is the backbone of modern manufacturing industry besides being a major industry in itself. Throughout the world, hundreds of million tons of metals go through metal forming processes every year. As much as 15 - 20 % GDP of industrialized nations comes from metal forming industry. Besides, it fulfills a social cause by providing job opportunities to the millions of workers. Metal forming industry, in general, is a bulk producer of semi-finished and finished goods and this is one reason that it is viable to undertake large-scale research and development projects because even a small saving per ton adds up to huge sums. Successful completion of this project will lead to capacity development in industrial partners for the development of High-Tech Machine Tools. This will allow them to compete with foreign manufactures that already have experience with such projects. This will turn contribute to Make in India initiative of the Indian government. The developed machine tool and process would help to produce components having small batch size with complex geometry. The Processes developed with this project will also facilitate quicker adaptation of Incremental Sheet Forming (ISF) as a mainstream technology. In long run, the results generated from the project will contribute directly and indirectly towards the enhancement of flexibility not only in the manufacturing of sheet metal forming processes but for manufacturing of components having complex geometry Beneficiaries of the developed technology include automobile, aerospace, defence, biomedical and nuclear sectors. For batch sized productions and sheet metal rapid prototyping, ISF present an exciting opportunity to produce complex geometry based sheet metal prototypes. With Adaptive Double Sided Incremental Forming (AdDSIF), sheet metal industry can become more flexible and capable. Especially, ISF can play a major in bringing down the costs of several medical implants. Most medical implants are designed uniquely for individual patients. When the implants are required to be in form of metal sheets, the cost of corresponding dies adds to the implant cost and renders is unaffordable to many. As ISF is a dieless forming process, the cost of dies can be avoided which is bound to make sheet metal implants much more affordable. In the age of ever increasing demand for flexible and digital manufacturing processes and machines, AdDSIF process and machine tool developed under this project is poised to play a major role towards adoption modern practices in metal forming industry. The output from this project will also help in positioning India as a bellwether of modern manufacturing

Next steps

1. Double sided forming strategies will be developed for experimentation 2. Experimental Campaign will commence once the Double Sided Incremental Forming (DSIF) experimental setup is available 3. Ultrasonic Spindle and setup for Ultrasonic Vibration Assisted Incremental Sheet Forming (UVaISF) will be fabricated within next 3 months 4. Strategies for UVaISF will be developed and will be implemented on the UVaISF setup 5. FEA models and Material models for AdDSIF and UVaISF are being developed 6. CAD/CAM module will be developed within next 6 months 7. Paradigm for Adaptive Double Sided Incremental Forming (AdDSIF) will be implemented by writing custom routines with API of CNC controller 8. A compliance device would be developed for facilitation of AdDSIF 9. A sentivity analysis would be carried out to optimize the process 10. After 6 months field testing with industrial collaborators will also commence 11. After Implementation of the final solution, the project will be documented and patents for the novelty would be filed

Publications and reports

1. Kumar, Pavan, and Tandon, Puneet, 'Estimation of Material Model Parameters from Mixed Loading Test for effective Simulation of Incremental Sheet Forming', International Conference on Modeling, Simulation and Control (ICMSC 39;17), World Congress on Engineering and Computer Science 2017 (WCECS 2017), San Francisco, USA, October 25-27, 2017, pp. 841-846 -(Presented by Puneet Tandon) 2.'Development of Low Frequency Vibration assisted Tool Path for Single Point Incremental Sheet Forming', Ashish Dubey, Shiv Kumar, Pavan Kankar and Puneet Tandon (manuscript under Preparation)

Patents

NA

Scholars and Project Staff

S. No.- Name- Designation- Date of Joining - Date of Release 1-Mr. Abdul Wahab Hashmi- Junior Research Fellow- September, 2017 - December, 2017 2-Mr. Rajkumar Mandal- Junior Research Fellow- September, 2017 April, 2018 3-Mr. Pididiprudhvi Raju- Junior Research Fellow- August, 2018 4-Mr. Pavan Kumar- Doctoral research scholar- May, 2017 5-Mr Aniket Nagargoje- Junior Research Fellow/Doctoral research scholar- June, 2018 6-Mr. Sanjog Patidar- Masters Student- June, 2017- June, 2018 7-Mr. Swarit Anand- Masters Student- February, 2018 8-Mr. Sitaram Modi- Masters Student- February, 2018 9-Mr. Nishant Manish- Masters Student- February, 2018 10-Miss. Amita Sahu-Masters Student- February, 2018 11-Mr. Mohammad Almas Khan- Under Graduate student- April, 2018

Challenges faced

In absence of a capable vendor, the procurement of components required for developing UVaISF setup was hindered. Presently, suitable vendors are identified and the procurement of components is in process. The setup would be ready by May 2019.

Other information

NA