Session: 03-04-02: Advanced Machining and Finishing Processes

Paper Number: 144723

144723 - Magnetorheological Finishing of 3d Printed Free-Form Aerofoiled Surfaces 

Polylactic acid (PLA) is a popular material in 3D printing due to its affordability, biodegradability, and ease of use. Applications in industries have been steadily increasing, driven by advancements in 3D printing technology and its material properties. Industries such as automotive, aerospace, and medical are increasingly integrating PLA-printed parts into their applications. The primary reason for this adoption of 3D printing is that it may produce custom parts with intricate geometries. In the present study, the 3D-printed aerofoil is taken as the 3D workpiece. Aerofoils are an essential component in aviation and fluid dynamics. The surface finish of aerofoils plays a crucial role in their performance. The streamlined surface finish enhances the aerofoil's efficiency in generating lift, provides stability in aircraft, and maximizes energy conversion in turbines. In fluid dynamics, a smooth surface finish minimizes drag, enhancing efficiency by reducing turbulence and frictional resistance. 

The magnetorheological finishing (MRF) process is used to improve the surface quality of the 3D-printed aerofoil. The MRF process reduces the stair-step effect generated by 3D printing. The MRF has controlled finishing forces to obtain the desired surface finish. Based on the controlled finishing forces, the material removal rate of the 3D-printed aerofoil has been investigated. The magnetic normal force, combined with the rotation of the tool and the swelling motion, removes the roughness peaks from the 3D aerofoil workpiece surface.

The MR polishing (MRP) fluid is used in the surface finishing process of the 3D aerofoil workpiece. The MRP fluid is made up of abrasive particles and electrolyte iron particles suspended in a base fluid. The MRP fluid changes its rheological properties when it comes into contact with the magnetic field. Finite element analysis (FEA) is used to analyze the desired magnetic flux intensity in the MRF process. During the MRF process, the maintained current is 2A with a working gap of 0.6 mm, and the rotating speed of the tool is 300 rpm. The initial surface roughness obtained by a confocal surface roughness profilometer after 3D printing an aerofoil at a layer thickness of 0.1 mm is Ra = 9.16 μm. The grinding process of 25 minutes is used to reduce the surface roughness to Ra = 0.2 μm. The MRF process of 40 minutes reduced the surface roughness to Ra = 0.08 μm. Scanning electron microscopy (SEM) is used to analize the surface characteristics of the aerofoil before and after the MRF process. The MRF process on 3D-printed aerofoil proves that the developed six-axis MRF setup is capable of removing the stair-stepping effect from the 3D workpiece surface.  The reduced surface roughness (Ra) of the aerofoil can enhance the aerodynamic performance by reducing drag and increasing lift, promoting laminar flow, and also reduces turbulent airflow.

Presenting Author: Anant Kumar Singh Thapar Institute of Engineering and Technology

Presenting Author Biography: Dr. Anant Kumar Singh is presently working as a professor in the Department of Mechanical Engineering at the Thapar Institute of Engineering and Technology, Patiala. He completed his Ph.D. degree full-time in the area of advanced finishing processes using magnetorheological (MR) fluids from IIT Delhi in 2013. During his Ph.D. work, he developed a new ball-end magnetorheological finishing process with a multi-axis motion control system. His research activities are focused mainly on advanced finishing and machining processes, nano-finishing using MR fluids, and automation in smart manufacturing. His teaching interests are industrial automation and mechatronics. He published over 95 research papers in international journals and conferences. Three patents have been granted in his area of research. He has supervised over 17 Master's and 6 Ph.D. dissertations in the area of MR fluid-based finishing methods and their application. He completed two sponsored research projects, and currently three are ongoing as a principal investigator funded by government agencies in India and the Thapar Institute. He visited outside India to present his research papers and chair sessions at various international conferences.

Authors:

Shubham Khatri Thapar Institute of Engineering and Technology
Surya Pratap Singh Thapar Institute of Engineering and Technology
Anant Kumar Singh Thapar Institute of Engineering and Technology