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reza-kashyzadeh--kazem
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Experimental and Numerical Study of Low Fatigue Cycle Behavior of Magnesium-Lithium Alloy
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholam Hossein (Supervisor) ; Kashyzadeh, Kazem Reza (Co-Supervisor)
Abstract
Application of light metals such as Magnesium alloys due to proper mechanical behavior is increasing in industries such as automotive, electronics and so on. In this project, ingot of Mg-9Li-1Zn alloy with 10 mm thickness were produced by casting, then hot rolled at 300oC to reach 2mm thickness. Annealing at 350oC for 3 hours resulted homogenous properties in the final sheet.Study of monotonic and cyclic behavior of Mg-Li alloy by experiments and FE simulation was the goal of this project. Experimental monotonic and cyclic test were carried out in order to obtain the hysteresis loops and cyclic stress-strain curve. The Chaboche constant were extracted from the experimental test and used to...
Developing a Method for Fatigue Life Assessment of Vehicle Biw by Considering Spot Welding Connections
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholamhossein (Supervisor) ; Chizari, Mahmoud (Supervisor) ; Reza Kashyzadeh, Kazem (Co-Supervisor)
Abstract
One of the most important considerations in the vehicle design procedure is the durability of the components. Among different parts of a vehicle, the body is the main load-bearing component and as a result, its durability is critical. Due to the expensive and time-consuming nature of fatigue tests, finite element based durability analysis is of great interest among automotive industry. The aim of this research is to provide an algorithm for a more accurate and efficient durability analysis of the vehicle body by considering inertia effects. By using the multi-body dynamics model of the full vehicle and the finite element model of the vehicle body, the vehicle body structure is analyzed from...
A new algorithm for fatigue life assessment of automotive safety components based on the probabilistic approach: The case of the steering knuckle
, Article Engineering Science and Technology, an International Journal ; Volume 23, Issue 2 , 2020 , Pages 392-404 ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In the present paper, the author has attempted to examine fatigue life of automotive safety components under axial variable amplitude loading conditions. To this end, the time components of stress tensor in the critical area of the knuckle and Liu-Zenner criterion were used to calculate the time history of equivalent stress. Then, the probability distribution function (PDF) of stress was extracted by applying the stress level counting technique. The Fourier curve fitting method was employed in order to formulate the PDF. Subsequently, the fatigue life of the component was estimated using the probabilistic approach. Finally, the results of the higher order of Fourier curve fitting and...
Failure strength of automotive steering knuckle made of metal matrix composite
, Article Applied Mechanics ; Volume 4, Issue 1 , 2023 , Pages 210-229 ; 26733161 (ISSN) ; Sharif University of Technology
MDPI
2023
Abstract
This article presents the static performance of composite steering knuckle due to drive on an equivalent road, including different types of roughness and maneuvers. To achieve this purpose, the driving of a full-vehicle model was simulated using the multi-body dynamics (MBD) method, and the imposed loads on connection points of the steering knuckle to different components of the suspension system were extracted considering various maneuvers. Next, CATIA software was used to prepare a smooth model of the steering knuckle by employing coordinate measuring machine (CMM) data. Stress analysis was performed under the maximum value of the loading history in finite element (FE) software....
Effect of Different Defects of Spot Welded Joint in Automotive Body on Fatigue Strength: Experimental and Numerical Investigation
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholamhossein (Supervisor) ; Mehmanparast, Ali (Supervisor) ; Reza Kashyzadeh, Kazem (Co-Supervisor)
Abstract
On average there are to resistance spot welding connections per vehicle. The quality of these welding directly affects the quality of the finished product and the strength of the vehicle against various loads, including road roughness, different maneuvers and even sudden impacts from accidents. During the spot welding process, unintentional failures occur due to the wrong choice of current, force and time. The aim of this study is to investigate the fatigue strength of three-sheets welding joints in numerical and laboratory methods, considering the defects of (Undersize weld, Stick, edge of sheet metal and Edge of sheet metal-SECANT) . For this purpose, a healthy spot welding model was first...
Experimental Study of the effect of vehicle velocity on the ride comfort of a car on a road with different types of roughness
, Article Innovative Manufacturing, Mechatronics and Materials Forum, iM3F 2020, 6 August 2020 through 6 August 2020 ; Volume 730 , 2022 , Pages 593-604 ; 18761100 (ISSN); 9789813345966 (ISBN) ; Amiri, N ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Vehicle speed control is one of the most important factors at increasing safety, reducing the number and severity of road accidents. Also, other factors such as inappropriate designing, the overuse of speed bumps, nonconformity to the prevailing standards of the world in construction, maintenance, and repair of roads can cause damage to the car suspension and consequently brings the discomfort of car occupants when crossing the actual road under different driving conditions (various speeds and maneuvers). In the present paper, the effect of different vehicle velocities on the comfort of occupants was investigated empirically. To this end, a passenger vehicle was driven at different constant...
Influence of conventional shot peening treatment on the service life improvement of bridge steel piles subjected to sea wave impact
, Article Journal of Marine Science and Engineering ; Volume 11, Issue 8 , 2023 ; 20771312 (ISSN) ; Chizari, M ; Sharif University of Technology
Multidisciplinary Digital Publishing Institute (MDPI)
2023
Abstract
The first goal of the current study is to estimate the fatigue life of the middle steel piles of an integrated bridge installed in water and subject to the impact of sea waves. In the following, the authors have tried to improve the service life of this critical part of the bridge, which is also the main purpose of the study. To this end, conventional shot peening, as one of the most well-known surface treatments, was used. Axial fatigue tests were performed on samples fabricated from IPE-220 steel piles in two states without and with shot peening surface treatment. Next, the modified S-N curve was entered into the finite element software to define the effect of shot peening treatment....
Improvement of HCF life of automotive safety components considering a novel design of wheel alignment based on a Hybrid multibody dynamic, finite element, and data mining techniques
, Article Engineering Failure Analysis ; Volume 143 , 2023 ; 13506307 (ISSN) ; Farrahi, G. H ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
The main aim of the present study is to improve the High-Cycle Fatigue (HCF) life of automotive safety components subjected to multi-input random non-proportional loading. A case study was conducted on the automotive knuckle as one of the high-critical mechanical components of the suspension and steering systems. The steering knuckle is subjected to the highest road- and steering-induced random loads that are exerted on several points (i.e., joints of knuckle with lower control arm, steering linkage, and Macpherson strut). Moreover, incorrect adjustment of wheel angles increases the intensity of road loads. In this regard, previous studies have shown that wheel angles affect the service time...
Surface layer nanocrystallization of carbon steels subjected to severe shot peening: Analysis and optimization
, Article Materials Characterization ; Volume 157 , 2019 ; 10445803 (ISSN) ; Unal, O ; Reza Kashyzadeh, K ; Sharif University of Technology
Elsevier Inc
2019
Abstract
Severe shot peening (SSP) process is widely used for surface nanocrysallization of a bulk material that demonstrates excellent mechanical properties compared with its coarse-grained equivalents. In this study, a plastically deformed surface was produced with nanostructured grains on different materials of AISI 1045, 1050, and 1060 carbon steels by means of SSP. Shot peening was applied with a wide range of Almen intensities and coverages. Optical microscopy, scanning electron microscopy, field emission scanning electron microscopy, high resolution transmission electron microscope observations, and X-ray diffraction analysis were employed to analyze the mechanism of grain refinement...
Efficiency analysis of shot peening parameters on variations of hardness, grain size and residual stress via taguchi approach
, Article Metals and Materials International ; Volume 25, Issue 6 , 2019 , Pages 1436-1447 ; 15989623 (ISSN) ; Unal, O ; Reza Kashyzadeh, K ; Sharif University of Technology
Korean Institute of Metals and Materials
2019
Abstract
In the present study, the main purpose is to detect the most key factors of shot peening (SP) process on the microhardness, grain size, and residual stress of AISI 1060 high carbon steel. The specimens were treated using various types of SP process namely conventional shot peening and severe shot peening. Several experiments were performed to study metallurgical and mechanical properties of AISI 1060 steel. Almen intensity and surface coverage from one side and microhardness, grain size, and residual stress from the other side were considered as input and output parameters for the design of experiment methodology, respectively. The L18(21and31) mixed level of Taguchi orthogonal array design...
Effects of drying temperature and aggregate shape on the concrete compressive strength: Experiments and data mining techniques
, Article International Journal of Engineering Transactions C: Aspects ; Volume 33, Issue 9 , 2020 , Pages 1780-1791 ; Ghorbani, S ; Forouzanmehr, M ; Sharif University of Technology
Materials and Energy Research Center
2020
Abstract
The main purpose of this paper is to assess the impact of the geometry and size of the aggregate, as well as the drying temperature on the compressive strength of the ordinary concrete. To this end, two aggregates with sharp and round corners were prepared in three different aggregate sizes. After preparing concrete samples, the drying operations were carried out in the vicinity of room temperature, cold wind, and hot wind. Next, the linear relationship between the concrete strength and the studied parameters was estimated using Multiple Linear Regression (MLR) method. Finally, the Taguchi Sensitivity Analysis (TSA) and Decision Tree Analysis (DTA) were applied in order to determine the...
Fracture toughness evaluation of 1.4841 bolt subjected to simultaneous effects of creep and hydrogen embrittlement phenomena using small punch test: A case study in a superheater of a petrochemical unit
, Article Engineering Failure Analysis ; Volume 144 , 2023 ; 13506307 (ISSN) ; Fallah, A ; Reza Kashyzadeh, K ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
Petrochemical components, especially superheater internal parts, work under very harsh conditions and in destructive environments, such as proximity to the high temperature caused by the fire, surrounded by corrosive gases, effects of hydrogen released by burning gas or incomplete burning. All these factors along with loading factors and other destructive phenomena such as creep at high temperatures directly affect the mechanical behavior of components. In other words, because of these conditions, the components will have different mechanical behavior compared to the non-operated components. In the present research, a case study was conducted on the failed bolts supporting long U-shaped...
Simultaneous effects of cutting depth and tool overhang on the vibration behavior of cutting tool and high-cycle fatigue behavior of product: experimental research on the turning machine
, Article International Journal of Advanced Manufacturing Technology ; Volume 122, Issue 5-6 , 2022 , Pages 2361-2378 ; 02683768 (ISSN) ; Borisovna, K. D ; Ghorbani, S ; Reza Kashyzadeh, K ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
One of the major challenges in the manufacturing parts, especially metals, is turning with good/excellent surface quality, which has a significant effect on the fatigue strength of the industrial components. Selecting incorrect or unsuitable values of machining parameters leads to vibration instability in the cutting tool and as a result, excessive roughness is created on the product’s surface. Therefore, one of the ways to reduce the roughness factor and increase the product fatigue life is to control the relative slip and vibration between the cutting tool and the workpiece. To achieve this goal, the authors attempted to investigate the simultaneous effects of tool overhang and cutting...
Effects of various strength defects of spot weld on the connection strength under both static and cyclic loading conditions: empirical and numerical investigation
, Article International Journal of Advanced Manufacturing Technology ; Volume 127, Issue 11-12 , 2023 , Pages 5665-5678 ; 02683768 (ISSN) ; Farrahi, G. H ; Reza Kashyzadeh, K ; Amiri, N ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
During the spot welding process, it is always possible to be made defects, and the most important reasons for defects can be due to incorrect settings of current, force, and time. In other words, at different time intervals depending on the working conditions of the welding machine (i.e., both manual and robotic machines), such as the erosion of the electrode head, it is necessary to optimize the welding parameters and apply the essential changes in the next settings. The presence of various defects reduces the quality and strength of spot welds and eventually structures, which is one of the main concerns in automotive, aerospace, and marine industries. Therefore, in the present research,...
Effects of conventional and severe shot peening on residual stress and fatigue strength of steel AISI 1060 and residual stress relaxation due to fatigue loading: experimental and numerical simulation
, Article Metals and Materials International ; October , 2020 ; Farrahi, G. H ; Reza Kashyzadeh, K ; Unal, O ; Gugaliano, M ; Bagherifard, S ; Sharif University of Technology
Korean Institute of Metals and Materials
2020
Abstract
Abstract: This study investigates and compares the effects of different shot peening treatments including conventional and severe shot peening on microstructure, mechanical properties, fatigue behavior, and residual stress relaxation of AISI 1060 steel. Shot peening treatments were applied with two Almen intensities of 17 and 21 A and a wide ranges of coverage (100%–1500%). Various microstructural observations were carried out to analyze the evolution of microstructure. Microhardness, residual stress and surface roughness measurements and also axial fatigue test were performed. Moreover, the extent of the residual stress relaxation during cyclic loading was investigated by means of XRD...
Effects of conventional and severe shot peening on residual stress and fatigue strength of steel aisi 1060 and residual stress relaxation due to fatigue loading: experimental and numerical simulation
, Article Metals and Materials International ; Volume 27, Issue 8 , 2021 , Pages 2575-2591 ; 15989623 (ISSN) ; Farrahi, G. H ; Reza Kashyzadeh, K ; Unal, O ; Gugaliano, M ; Bagherifard, S ; Sharif University of Technology
Korean Institute of Metals and Materials
2021
Abstract
Abstract: This study investigates and compares the effects of different shot peening treatments including conventional and severe shot peening on microstructure, mechanical properties, fatigue behavior, and residual stress relaxation of AISI 1060 steel. Shot peening treatments were applied with two Almen intensities of 17 and 21 A and a wide ranges of coverage (100%–1500%). Various microstructural observations were carried out to analyze the evolution of microstructure. Microhardness, residual stress and surface roughness measurements and also axial fatigue test were performed. Moreover, the extent of the residual stress relaxation during cyclic loading was investigated by means of XRD...
Fatigue life analysis in the residual stress field due to resistance spot welding process considering different sheet thicknesses and dissimilar electrode geometries
, Article Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications ; Volume 237, Issue 1 , 2023 , Pages 33-51 ; 14644207 (ISSN) ; Farrahi, G ; Ahmadi, A ; Minaei, M ; Ostad Rahimi, M ; Barforoushan, S ; Sharif University of Technology
SAGE Publications Ltd
2023
Abstract
A typical vehicle body contains many 3-sheet spot-welded connections with different sheet thicknesses. In addition, the use of dissimilar electrode geometries is extremely common in the automotive industry. These two factors lead to an asymmetric spot weld with asymmetric residual stress distribution and heat-affected zone. This asymmetry has considerable effects on the fatigue behavior of these joints. Although many previous studies were dedicated to the analysis of spot welds, consideration of different electrode geometries and fatigue analysis of 3-sheet spot-welded joints are absent in the literature. To this end, in the present paper, the resistance spot weld process of three-sheet low...
Experimental Investigation of the Effects of Wing Aspect ratio and its distance from the Tail on the Aerodynamic parameters at high A.O.A
, M.Sc. Thesis Sharif University of Technology ; Soltani, Mohammad Reza (Supervisor) ; Hejranfar, Kazem (Supervisor)
Abstract
In recent years, requirement to increase projectile performance, leads to a great interest in high angle of attack Aerodynamics. Projectile Maneuverability is a concept which is defined by having the capability to perform at high angles of attack while maintaining attached flow over the tail, rather than a capability of performing a mission in minimum possible duration. Interaction between body, wing and tail vortices can delay vortex breakdown over the wing and as a result may enhance projectile maneuverability. Studies show that wing aspect ratio and tail location have a remarkable influence on the vortices interaction and thus projectile maneuverability. In the present study, a series of...
Failure analysis of bolt connections in fired heater of a petrochemical unit
, Article Engineering Failure Analysis ; Volume 92 , 2018 , Pages 327-342 ; 13506307 (ISSN) ; Chamani, M ; Reza Kashyzadeh, K ; Mostafazade, A ; Mahmoudi, A. H ; Afshin, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The main function of a fired heater in a petrochemical site is to produce supersaturated steam. Due to extremely difficult working conditions and high temperatures, there is a very high probability of failures in different parts of a fired heater. In the fired heater under study, tube guides are frequently damaged due to malfunctions and fractures in bolt connections. To investigate the nature of such fractures, Computational Fluid Dynamics (CFD), Finite Element (FE) method, Charpy impact test and fractography were used. To obtain the temperature of various components of the fired heater, a CFD analysis was carried out by considering the combustion process and modeling the central and side...
Investigation of the Spray Pattern in the Air Flow Induced by Coaxial Rotors Used for Pesticide Spraying
, M.Sc. Thesis Sharif University of Technology ; Morad, Mohammad Reza (Supervisor) ; Hejranfar, Kazem (Supervisor)
Abstract
The production of agricultural products is one of the most important human economic activities. The issue of mechanized and optimal use of pesticides is vital for human health and the environment, and the use of helicopters makes this possible. Although spray-based systems in helicopters are one of the most effective ways to produce agricultural products, it is still unclear how droplet movement in aerial spraying is affected by the complex downwash flow created by rotors. Modeling agricultural air spray to identify the spray trend of droplets in the air stream, downwash flows, and consequent vortices has attracted more attention as a result of the development of computational fluid...