Some Insights on Combined Turning-Burnishing (CoTuB) Process on Workpiece Surface Integrity

Anis Rami,Fathi Gharbi,Salem Sghaier,Hedi Hamdi 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.1

This paper deals with a combined manufacturing process called Combined Turning-Burnishing (CoTuB) that performs turning and ball-burnishing simultaneously on the same machine tool. This innovative process aimed to enhance surface quality and integrity by exploiting rough turning conditions. Consequently, this implies an increase in productivity when compared to conventional surface treatment processes. For this reason, a device was manufactured in order to hold both commercial cutting and burnishing tools to carry out the removal material and the surface mechanical treatment processes simultaneously and under the same operation. As the design of CoTuB device sets the cutting tool ahead of the ball, turning is followed by burnishing operation along the manufactured surface. It has been depicted experimentally that a considerable improvement in surface quality could be achieved using the new combined process under suitable process parameters. Burnishing force, Ball burnishing diameter and depth of cut are independent parameters. In order to carry out a parametric process study, several experiments based on Taguchi method were performed. The aim is to identify the optimal turning/burnishing parameters when treating AISI 4140 steel. This helps to get a compromise between the optimal arithmetic surface roughness (Ra), the compressive residual stress state and the micro-hardness (μH).

Effect of Thermal Radiation on MHD Mixed Convective Heat Transfer Adjacent to a Vertical Continuously Stretching Sheet in the Presence of Variable Viscosity

A. M. Salem,Rania Fathy 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.6

An analysis is presented to study the combined free-forced convective laminar boundary layer flow adjacent to a vertical continuously stretching sheet in the presence of a magnetic field with variable viscosity and thermal radiation. The velocity and the temperature of the sheet were assumed to vary in a power law form, that is, uw= Bxm and Tw(x) − T∞ = Axn. The governing equations for the problem were changed to dimensionless ordinary differential equations by using a similarity transformation. The transformed governing equations in the present study were solved numerically by using the Runge-Kutta and Shooting method. A comparison between the analytical and the numerical solutions has been included. The effects of the variable viscosity parameter, the mixed convection parameter G*=Frx Re2x, the radiation parameter N and the magnetic field parameter M are discussed through graphs. Graphical results illustrating interesting features of the physics of the problem are presented and discussed.

Management based on grading of animation deformity following implant-based subpectoral breast reconstruction

Raghavan Vidya,Habib Tafazal,Fathi Salem,Fahad Mujtaba Iqbal,Tapan Sircar 대한성형외과학회 2018 Archives of Plastic Surgery Vol.45 No.2

Subpectoral breast reconstruction using implants and meshes have been used widely in Europe, the United States and the United Kingdom. Although this technique has several advantages, animation deformity is a well-documented problem. We propose a new grading system to classify breast animation in patients undergoing subpectoral implant based breast reconstruction. We also discuss different techniques to avoid and correct animation deformity.

Management based on grading of animation deformity following implant-based subpectoral breast reconstruction

Vidya, Raghavan,Tafazal, Habib,Salem, Fathi,Iqbal, Fahad Mujtaba,Sircar, Tapan Korean Society of Plastic and Reconstructive Surge 2018 Archives of Plastic Surgery Vol.45 No.2

Subpectoral breast reconstruction using implants and meshes have been used widely in Europe, the United States and the United Kingdom. Although this technique has several advantages, animation deformity is a well-documented problem. We propose a new grading system to classify breast animation in patients undergoing subpectoral implant based breast reconstruction. We also discuss different techniques to avoid and correct animation deformity.

Outcome of complete acellular dermal matrix wrap with polyurethane implant in immediate prepectoral breast reconstruction

Naemonitou, Foteini,Mylvaganam, Senthurun,Salem, Fathi,Vidya, Raghavan Korean Society of Plastic and Reconstructive Surge 2020 Archives of Plastic Surgery Vol.47 No.6

Background Polyurethane implants have been used on and off in breast reconstruction since 1991 while prepectoral breast reconstruction has gained popularity in recent times. In this study, we present our outcomes from the use of acellular dermal matrix (ADM) complete wrap with polyurethane implants in prepectoral breast reconstruction. Methods This is a retrospective review of prospectively maintained database from 41 patients receiving complete ADM wrap with prepectoral polyurethane implants over a 3-year period. Selection criteria were adapted from a previous study (4135 Trust Clinical Audit Database) evaluating prepectoral reconstruction with Braxon matrices. Patient demographics, operative data, surgical complications, and outcomes were collected and analyzed. Results A total of 52 implant reconstructions were performed in 41 patients with a mean follow-up of 14.3 months (range, 6-36 months). The overall reported complication rates including early (less than 6 weeks) and late complications. Early complications included two patients (4.9%) with wound dehiscence. One of which had an implant loss that was salvageable. Another patient (2%) developed red-breast syndrome and two women (4.9%) developed with seroma treated conservatively. Late complications included one patient (2%) with grade II capsular contraction, 12 patients with grade I-II rippling and two patients (4.9%) with grade III rippling. Conclusions We present our experience of prepectoral polyurethane implant using complete ADM wrap. This is one of the few papers to report on the outcome of the prepectoral use of polyurethane in immediate implant-based breast reconstruction. Our early observational series show satisfactory outcome and long-term results are warranted by a large multicenter study.

Enhanced extraction of copper and nickel based on the Egyptian Abu Swayeil copper ore

Somia T. Mohamed,Abeer A. Emam,Wael M. Fathy,Amany R. Salem,Amr B. ElDeeb 한국분석과학회 2024 분석과학 Vol.37 No.1

The continuous increasing of the global demand of copper and nickel metals raises the interest indeveloping alternative technologies to produce them from copper sulfide ore. Also, in line with Egypt's vision2030 for achieving the sustainable socioeconomic development which aims at developing alternative and ecofriendlytechnologies for processing the Egyptian ores to produce these strategic products instead of its importing. These metals enhance the advanced electrical and electronic industries. The current work aims at investigatingthe recovery of copper and nickel from Abu Swayeil copper ore using pug leaching technique by sulfuric acid. The factors affecting the pug leaching process including the sulfuric acid concentration, leaching time andtemperature have been investigated. The copper ore sample was characterized chemically using X-rayfluorescence (XRF) and scanning electron microscope (SEM-EDX). A response surface methodology developsa quadratic model that expects the nickel and copper leaching effectiveness as a function of three controllingfactors involved in the procedure of leaching was also investigated. The obtained results showed that themaximum dissolution efficiency of Ni and Cu are 99.06 % and 95.30%, respectively which was obtained atthe following conditions: 15 % H2SO4 acid concentration for 6 hr. at 250 ℃. The dissolution kinetics of nickeland copper that were examined according to heterogeneous model, indicated that the dissolution rates werecontrolled by surface chemical process during the pug leaching. The activation energy of copper and nickeldissolution were 26.79 kJ.mol−1 and 38.078 kJ.mol−1 respectively; and the surface chemical was proposed asthe leaching rate-controlling step.