Ultrasonic Assisted Deep Drilling of Super-Alloy and Comparison With Electro Discharge Drilling Method

, M.Sc. Thesis Sharif University of Technology Baghlani, Valid (Author) ; Akbari, Javad (Supervisor)

Abstract

Drilling super alloys with a good hole quality and acceptable surface finish is a constant challenge in modern industries dealing with such materials. Ultrasonic assisted drilling is a modern and nonconventional method of drilling which has attracted many researchers attention recently. In this study deep drilling on Inconel 738 LC is done using ultrasonic assisted drilling technique and the results are compared with those of Electro Discharge Machininng or EDM method. The results show that Ultrasonic Assisted Drilling or UAD is an appropriate alternative for EDM of Inconel. The whole process time is decrease dimensional accuracy is improved and surface roughness is decreased significantly....

Discrete optimum design of truss structures by an improved firefly algorithm

, Article Advances in Structural Engineering ; Vol. 17, issue. 10 , 2014 , p. 1517-1530 Baghlani, A ; Makiabadi, M ; Sarcheshmehpour, M ; Sharif University of Technology

2014

Abstract

This paper presents an improved firefly algorithm (FA) for fast optimization of truss structures with discrete variables. The enhanced accelerated firefly algorithm (AFA) is a simple, but very effective modification of FA. In order to investigate the performance and robustness of the proposed algorithm, some benchmark (structural optimization) problems are solved and the results are compared with FA and other algorithms. The results show that in some test cases, AFA not only finds lighter structures compared to other algorithms, but also converges faster. In the rest test cases, the optimal solutions are found with very less computational effort. The study also shows that the proposed AFA...

Ultrasonic assisted deep drilling of Inconel 738LC superalloy

, Article Procedia CIRP, Leuven ; Volume 6 , April , 2013 , Pages 571-576 ; 22128271 (ISSN) Baghlani, V ; Mehbudi, P ; Akbari, J ; Sohrabi, M ; Sharif University of Technology

2013

Abstract

Superalloys have a poor machinability and are often drilled using Electro Discharge Machining (EDM) methods. However EDM is a time-consuming process and has low surface integrity. Ultrasonic Assisted Drilling (UAD) technology is a modern method of drilling such materials. Although this method has very high capabilities, it has not been introduced widely to industry. In this study a special horn is designed and used to apply both rotation and vibration to drill bits. It can transfer power with high efficiency and has the capability to change tools easily. The setup is used to conduct deep drilling tests on Inconel 738LC with depth-to-diameter ratio of 10. The effect of ultrasonic vibration...

An optimization technique on ultrasonic and cutting parameters for drilling and deep drilling of nickel-based high-strength Inconel 738LC superalloy with deeper and higher hole quality

, Article International Journal of Advanced Manufacturing Technology ; Volume 82, Issue 5-8 , 2016 , Pages 877-888 ; 02683768 (ISSN) Baghlani, V ; Mehbudi, P ; Akbari, J ; Zal Nezhad, E ; Sarhan, A. A. D ; Hamouda, A. M. S ; Sharif University of Technology

Springer-Verlag London Ltd 2016

Abstract

In this research work, an ultrasonic assisted drilling system is employed to apply both rotation and vibration to drill bits. The transducer horn transfers power very efficiently and changes tools effortlessly. The setup used to conduct drilling tests is Inconel 738LC with depth-to-diameter ratios from 2 to 10 by conventional drilling (CD), ultrasonic assisted drilling (UAD), and electro discharge drilling (EDD). The effects of ultrasonic vibration amplitude, spindle speed, and number of steps to drill each hole on machining force and surface roughness in UAD are investigated. The results demonstrate not only a significant improvement in tool life (by applying ultrasonic vibration to the...