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Mughal KH, Qureshi MAM, Jamil MF, Ahmad S, Ahmad Khalid F, Qaiser AA, Maqbool A, Raza SF, Zhang J. Investigation of hybrid ultrasonic machining process of Nomex honeycomb composite using a toothed disc cutter. ULTRASONICS 2024; 141:107343. [PMID: 38754149 DOI: 10.1016/j.ultras.2024.107343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024]
Abstract
Nomex honeycomb composite (NHC) has been increasingly used in the automotive, aerospace and defence applications due to its excellent thermal and mechanical properties. Its complex cellular hexagonal thin-walled configuration along with heterogeneous, soft and brittle nature pose substantial processing defects such as burr formation, tearing of walls, surface roughness, dimensional inaccuracy and low machining quality during conventional machining (CM). These surface defects have a substantial influence on the operating life and functional performance of its sandwiched structural members. Hybrid ultrasonic vibration assisted machining (HUSVAM) technology has been introduced to overcome such limitations. For an in depth research on HUSVAM of NHC using ultrasonic toothed disc cutter (UTDC), three dimensional finite element model was developed and experimental validation was carried out. The numerical simulation and experimental results were found to be in good agreement with one another. The influence of various machining parameters including the ultrasonic tool vibration amplitude (UTVA), feed rate (FR), depth of cut (DoC) and spindle angular speed (SAS) on NHC cutting forces, chip formation and surface quality was investigated using both HUSVAM and CM techniques. Furthermore, stresses, deformation and forces near tool-workpiece interaction along with the surface topography and morphologies were also analysed and compared for various operating conditions. A reduction in the cutting forces was found with the increase of SAS and UTVA (up to 65.47 % and 65.74 %, respectively). Although, the cutting forces were observed to increase by increasing the DoC and FR (up to 159.45 % and 126.33 %, respectively). DoC has a greater impact on the cutting forces among all machining parameters according to 4 levels, 4 factors (L16) orthogonal experiments based on Taguchi method. The results show that the chip formation and machining quality of NHC core can be improved with HUSVAM technique using UTDC. HUSVAM also reduced the cutting forces (up to 73 %) compared to CM. The ultrasonic toothed disc cutter generated large number of burr with very short length, no tearing defects and no uncut fibers as observed from scanning electron microscopy of NHC hexagonal cell structure, walls and triple points. A burr formation of less than 10 % was realized during HUSVAM of NHC cores for Fx≤3N, while it was found up to 20 % if Fx>3N, compared to at least 40 % during CM. The finite element model developed can be used to investigate the influence of HUSVAM on modern difficult to machine materials for enhanced surface quality.
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Affiliation(s)
- Khurram Hameed Mughal
- Mechanical Engineering Department, University of Engineering and Technology, Lahore 54890, Pakistan; Mechanical Engineering Department, The University of Lahore, Lahore 54000, Pakistan.
| | | | - Muhammad Fawad Jamil
- Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipment and Control, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Shehzad Ahmad
- Mechanical Engineering Department, Muhammad Nawaz Sharif University of Engineering & Technology, Multan, Pakistan
| | - Fazal Ahmad Khalid
- Faculty of Materials and Chemical Engineering, GIK Institute of Engineering Sciences and Technology, Topi 23640, Pakistan
| | - Asif Ali Qaiser
- Polymer and Process Engineering Department, University of Engineering and Technology, Lahore 54890, Pakistan
| | - Adnan Maqbool
- Department of Metallurgical & Materials Engineering, University of Engineering and Technology, Lahore 54890, Pakistan
| | - Syed Farhan Raza
- Industrial & Manufacturing Engineering Department, University of Engineering and Technology, Lahore 54890, Pakistan
| | - Jianfu Zhang
- Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipment and Control, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
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Dong Y, Chen C, Lin S. Coupled vibration of a radially polarized piezoelectric cylinder with a co-axial elastic cylinder of varying height. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:511-522. [PMID: 38252796 DOI: 10.1121/10.0024358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024]
Abstract
The cylindrical piezoelectric transducer has the advantages of large radiation area, high electromechanical coupled coefficient, and omni-direction radiation along the radius. In this paper, a piezoelectric transducer consisting of a radially polarized piezoelectric cylinder and an outer metal cylinder of varying height is presented. The metal cylinder of varying height is approximated as the radial superposition of multiple uniform height metal cylinders, and the equivalent impedance of the transducer's coupled vibration is obtained by using the impedance matrix method, and then the resonance frequency, anti-resonance frequency, effective electromechanical coupled coefficient, and displacement amplification coefficient are obtained. In this paper, the relationship between the vibration characteristics of the cylindrical piezoelectric transducer and its geometric dimensions is studied. An experimental sample of the transducer is fabricated and assembled, and its electrical impedance curve is measured. The measured results are in good agreement with the simulation results and the theoretical calculation results. The displacement distribution of the radiation surface of the transducer at resonance frequency is measured, which verifies that the two coupled vibration modes of the transducer can be effectively excited.
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Affiliation(s)
- Yilei Dong
- Shaanxi Key Laboratory of Ultrasonics, Institute of Applied Acoustics, Shaanxi Normal University, Xi'an 710119, China
| | - Cheng Chen
- Shaanxi Key Laboratory of Ultrasonics, Institute of Applied Acoustics, Shaanxi Normal University, Xi'an 710119, China
| | - Shuyu Lin
- Shaanxi Key Laboratory of Ultrasonics, Institute of Applied Acoustics, Shaanxi Normal University, Xi'an 710119, China
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