Ayad M. Takhakh

Al-Nahrain University · Department of Mechanical Engineering

Stroke is a common worldwide health problem and a crucial contributor to gained disability. The abilities of people, who are subjected to stroke, to live independently are significantly affected since affected upper limbs' functions are essential for our daily life. This review article focuses on emerging trends in BCI-controlled rehabilitation tec...

The most important way for joining the non-welding aluminum alloy is Friction stir spot welding. Three parameters effect on efficiency of welding: tool shape, rotational speed, and plunged time, are chosen to study for welding 6061T6 aluminum alloy. Each of the above parameters has three variables as: pin shapes (square, cylinder, and hexagonal), p...

During the last few years, smart materials like shape-memory polymers (SMPs) have attracted great attention from manufacturers and researchers due to their ease of formability and functionality. One of the most recent advanced techniques for manufacturing SMPs to create recoverable objects is additive manufacturing (3D printing). The factors that s...

This article introduced a three-dimension CAD model of a prosthesis testing platform using SolidWorks software to conduct a kinematic and dynamic analysis of the transfemoral prosthesis of the virtual model. Concurrently, the event-based motion simulation (EBMS) procedure was carried out on the CAD model. The concept of the operational strategy of...

The main problem of the prosthetic limb design is the ability to test recently developed devices on amputee and testing in dangerous circumstances. In the present study, a virtual model of trans-femoral prosthesis test platform was designed using SolidWorks® 2018 Software that simulates a dynamic model during the gait cycle. The purpose of this pro...

The main problem with designing prostheses is the ability to assess newly manufactured devices on patients under unsafe conditions. Some of the issues that obstruct the testing process of the prosthetic limbs on amputees are informed consent, safety straps, and inadequate repetitiveness. This paper introduced a literature study regarding prosthesis...

The improvement of the topological properties in contacts surfaces has been drawn the attention of many commercial firms to reduce energy waste resulting from the influence of friction and wear in combustion engines. These motivations were sufficient for adding nanoparticles upon lubricants to improve their performances. Analysis of nano specimens'...

Modifying buckling behavior of the composite structure has been investigated in the recent few years with different reinforcement fiber and powder materials and nanomaterials. It can be seen from previous studies that the addition of nanomaterials leads to a significant modification in the buckling behavior of structure by using a low mount of nano...

The effect of welding parameters on mechanical properties of aluminum alloy AA 2024-O Friction stir-welded (FSW) joints was investigated in the present study. Taguchi method was used to evaluate the optimum value of process parameters from tensile tests using nine experiments designed according to the matrix proposed by the scientist Taguchi for th...

Friction Stir Processing (FSP) technology was wielded to output the Al7075/ Al2O3 surface composite. The effects parameters of processing method on particle distribution have been studied. The microstructure and mechanical characteristics of the samples were examined using the optical microscope, SEM and hardness examination. Acquired consequences,...

This paper presents a study of the effects of temperature, curing time and silver nano-particles (AgNPs) on the concentration of the PVP/PVA nano composites on shear force of adhesive nano-joining (ANJ). Low temperature (LT) ANJ of copper–copper (Cu–Cu) at the temperature values of 200, 215, 225, 240 and 275°C and curing times of 10, 20 and 30 minu...

in this study, the mechanical, microstructure and corrosion properties of Nickel-Titanium-Copper shape recovery alloys were investigated. The alloy was prepared by the powder metallurgy method, where powders of 50% Titanium, 47 % Nickel and 3% Cupper were mixed and cold compacted at (600,700 and 800) MPa to form cylindrical samples of (11mm diamete...

This paper investigates the effect of heat treatment on the mechanical properties (yield and ultimate strength, elongation, hardness, and modulus of elasticity) and dynamic characteristics (natural frequency and dynamic response) under impulse loading for 6061 and 2024 aluminum alloys in O, T4, and T6 treatment conditions to study the effect of hea...

This study deals with evaluation of smart economic transfemral Prosthetic consist of a new design and manufacturing of knee joint and design and manufacture of a simple electronic circuit that is programmed to control the muscle pressure on the sensor during movement and transfer the voltage of force sensor after processing in microcontroller to th...

The muscles of the leg are amplified by athletes while exercising. In the case of athletes with limb limbs, this causes irritation and pain in the area of contact with the socket. In order to solve this problem, the subject was studied carefully and the amount of muscle spasm and pressure generated during the different activities of the amputee , T...

In present work, the improving of mechanical properties for welded joint of Al7075-T651 is done using friction stir processing for joint surface by adding SiC particles into surface joint. Strength properties and microhardness of the processing joints has been investigated and compared with welded joint of alloy Al7075-T651. It is recorded that the...

This research study an experimental and optimization work of the effect of moisture on the shear strength of adhesive joints and improvement by adding variable concentration of PVA to PVP. In this work, shear strength samples from Cu-Cu and the adhesive made from dissolving 16 grams of polyvinyl pyrrolidone (k30) and 8 grams of polyvinyle Alcohol i...

A well-designed lower limb prosthesis is necessary in order to permit an amputee to repeat to healthy locomotion. The aim of this study is to enhance the passive prosthesis to a microcontroller-based transfemoral prosthesis which was unable to reach the designated rotational speed intended for a functional use, and had low cost. The enhancement foc...

This work involved experimental study of tensile and fatigue properties for below knee prosthetic sockets materials fabricated using vacuum molding technique. The composite materials are composed of number of carbon-fiber layers (8 layers) and (11 layers) carbon fiber with perlon. The (Ground Reaction Force (GRF), Center of Pressure (COP) and press...

FRICTION STIR PROCESSING (FSP) IS A DEVELOPING NEW, VITALITY PROFICIENT AND GREEN PROCESSING METHOD TO CREATE COMPOSITES SURFACE, WHICH DEPENDS ON THE ADDITIVE AND BASE MATERIALS AND ITS CONTACT MIX BONDING. APPLICATION OF ALUMINUM ALLOYS IN MARINE, AEROSPACE FRAMES, STRUCTURES, TRANSPORTATION, AND EXTREMELY STRESSED PARTS. IN THIS BOOK , COMPOSIT...

This research study an experimental and optimization work of the effect of temperature, curing time and copper concentration on the shear strength of adhesive joints by mixing Polyvinyl Pyrrolidone PVP K30 and polyvinyle alcohol with copper. In this research, shear strength of the adhesive made from dissolving 16 g of Polyvinyl Pyrrolidone PVP (K30...

Knee ankle foot orthoses (KAFOs) are used by paraplegia patients with low level spinal cord injury and having well control of the stem muscles. Four layers of carbon fiber with C- orthocryl lamination resin are used for manufacturing the knee ankle foot orthoses in this work. The mechanical properties of most of the components materials were estima...

Four types of laminated composite materials are tested experimentally in order to estimate the fatigue characteristics and investigation of the mechanical properties for a manufactured symes prosthetic socket. The socket is made of lamination 80:20 matrix reinforced by four types of reinforcement fibers; the first type includes (4perlon, 3carbon fi...

In this work, three types of laminated composite materials used for experimental study to investigate the tensile and fatigue properties of partial foot prosthetic socket which fabricated by using vacuum pressure system. The composite material matrix was Lamination 80:20and reinforced with nine types of laminations (perlon, fiber glass and carbon)....

In this study a Nickel-Titanium-Cupper shape memory alloys was manufactured by powder metallurgy (PM) technique, powder mixture of 50% Ti , 47% Ni and 3% Cu was prepared by mixing for two hours and compacted in a press machine using various compacting pressure (600, 700 and 800) MPa , sample was then sintered for 5 hrs in an electrical tube vacuum...

This study includes two main parts: The first part includes the process of manufacturing and testing partial foot orthosis for a patient suffering from partial foot amputation. The orthosis was manufactured from lamination Perlon-Carbon-Perlon (4-2-4) and then tested with Force plate and F-Socket. The patient was tested in two cases: the first with...

In the present work, composite surface based on AA 7075-T651 matrix reinforced with micro-sized particles of silicon carbide (SiC) has been fabricated by Friction stir processing (FSP). The micorhardness of the processed surface has been investigated and compared with that of base alloy AA 7075-T651. It is found that the friction stir processed sam...

This work covered the experimental program to obtain the mechanical properties of the ankle Foot Ortheses (AFO) composite materials by using tensile, flexural and fatigue tests. They are composed of number of layers (12 layers) perlon with two lyers of carbon-fiber and (10 layers) without carbon fiber. Also, the Ground Reaction Force (GRF), Center...

Friction Stir Welding (FSW) is one of the most effective solid states joining process, FSP is used to modify the microstructure of FSW welded zone. These processes used in many applications that require sheet forming process. In comparison to other welding processes FSW have better formability.The objective of this experiment was to show the effect...

This study focuses on the manufacturing of Nickel-Titanium-Cupper shape memory alloys using powder metallurgy (PM) method, 50% Ti, 47% Ni and 3% Cu powder mixture was prepared by mixing in a ball mill for two hours and compacted in a press machine using various compacting pressure (600, 700 and 800) MPa, samples was then sintered in an electrical t...

Abstact Friction stir processing is a new method of changing the properties of a metal through intense, localized plastic deformation ,this process mixes the material without changing the phase (by melting or otherwise) and creates a micro structure with fine, equiaxedgrains, It is used to improve the micro structural properties of metals. In this...

In this study a Ni-Ti-Cu shape memory alloy was prepared by powder metallurgy (PM) technique, various compacting pressure of (600, 700 and 800) MPa and sintering temperature of (850˚C, 900˚C and 950˚C) were used, Shape Effect (strain recovery), porosity , microhardness ,X-ray diffraction ,energy dispersion x-ray (EDX), scanning electron microscope...

The effect of Cu addition on the physical and mechanical properties of Nickel-Titanium (weight percentage ) shape memory alloy were investigated , density , porosity , compression strength ,Shape Effect (strain recovery), ,micro-hardness , Conducted to estimate the Cu effect ,a Different amount of Cu (2%,5%,10% ) weight percent were added with diff...

In this study a Ni-Ti-Cu shape memory alloy was prepared by powder metallurgy (PM) technique, various compacting pressure of (600, 700 and 800) MPa and sintering temperature of (850˚C, 900˚C and 950˚C) were used, Shape Effect (strain recovery), porosity , microhardness ,X-ray diffraction ,energy dispersion x-ray (EDX), scanning electron microscope...

In this work, plastic materials (polypropylene) are used for manufacturing ankle foot orthoses (AFO) with drop foot fabricated using vacuum molding technique. The tensile test results showed that the mechanical properties for polypropylene were, Ϭy= 24.73Mpa Ϭult=35.76 MPa Ϭb max=67.66Mpa and Elongation at Break=38.26mm. The data of gait cycle (Gro...

Friction stir processing is a may be regarded as new method of changing the properties of a metal through intense, localized plastic deformation ,this process mixes the material without changing the phase (by melting or otherwise) and creates a micro structure with fine, equiaxedgrains, It is used to improve the micro structural properties of metal...

In this work, an investigation has been carried out on Friction stir welding (FSW) and friction stir processing (FSP) of 3mm thick plates of AA5086-H32 aluminium alloy using high carbon high chromium alloy steel tool with a thread tool pin shape. The process variable are welding type (FSW and FSP) and rotational speed which consist of three differe...

Friction stir processing is a new method of changing the properties of a metalthrough intense, localized plastic deformation,this process mixes the material without changing the phase(by meltingor otherwise) and creates a microstructurewith fine, equiaxedgrains, It is used to improve the microstructural properties ofmetals.In this paper , the enhan...

The effect of Sn addition on the physical and mechanical properties of Cu-13%Al-4%Ni (in weight percentage) shape memory alloy manufactured by powder metallurgy technique,the master alloys and Sn added alloys manufactured by powder metallurgy method in order to improve the alloys properties because this manufacturing process takes near net theoreti...

Friction stir processing is a new method of changing the properties of a metal through intense, localized plastic deformation ,this process mixes the material without changing the phase (by melting or otherwise) and creates a microstructure with fine, equiaxedgrains , It is used to improve the microstructural properties of metals. In this paper , t...

TThis paper deals with calculate stresses in Knee-Ankle-Foot-Orthosis as a result of the effect vibration during gait cycle for patient wearing KAFO .Experimental part included measurement interface pressure between KAFO and leg due to action muscles and body weigh on Orthosis. also measurement acceleration result from motion of defected leg by acc...

Cu-Al-Ni shape memory alloy specimens has been fabricated using powder metallurgy technique with tube furnace and vacuum sintering environment , three range of Nb powder weight percentage (0.3,0.6,0.9)% has been added. Micro hardness and sliding wear resist has been tested followed by X-ray diffraction, scanning electron microscope (SEM) and energy...

A standard knee-ankle-foot orthosis (KAFO) is typically prescribed to support the limb during locomotion, during which (KAFO) is used for people with isolated quadriceps weakness or paralysis. In this paper the measurement applied on girl undergoing palsy children in her left leg as a case study. The first pathological concern is of age, weight, le...

Cu-Al-Ni shape memory alloy specimens has been fabricated using powder metallurgy technique with vacuum sintering environment, three rang of Ta powder weight percentage (0.3,0.6,0.9)% has been added. Micro hardness and sliding wear resist has been tested followed by X-ray diffraction, SEM and EDX for micro structure observation. The experimental te...

The effect of welding parameters on mechanical properties of aluminum alloy 3003 H14 Friction stir-welded (FSW) joints were investigated in the present study. Different welded specimens were produced by employing variable rotating speeds (1000, 1250, 1500, 2000 r.p.m.), and welding speeds (20, 40, 60, 80 mm/min). Microhardness measurements and tens...

The aim of the present study is to investigate the influence of thermal variables on the as-cast microstructure of hypoeutectic and eutectic Al–Si alloys and to establish correlation between the solidification thermal parameters and interparticle spacing for Al–12%Si alloy during the unidirectional solidification. New relationships are suggested ba...

AA3003-H14 aluminum alloy plates were welded by friction stir welding and TIG welding. Fatigue properties of the welded joints were evaluated based on the superior tensile properties for FSW at 1500 rpm rotational speed and 80 mm/min welding speed. However, there is not much information available on effect of welding parameters with evolution of fa...

ABSTRACT A friction stir spot welding (FSSW) process is an emerging solid state joining process in which the material that is being welded does not melt. In this investigation an attempt has been made to understand the effect of tool shoulder diameter on the mechanical properties of the joint. For this purpose four welding tools diameter (10, 13,...

Fatigue characteristics of as-cast acicular ductile iron (ASGI) produced by alloying and controlled cooling and as-rolled 42CrMo4 steel were studied. Rotating bending fatigue tests at a stress ratio of R = -1 was employed. Tests included constant stress amplitude loading, variable stress amplitude high-low, low-high loading and coaxing. S - N curve...

Experimental and numerical study has been achieved on a hypoeutectic Al-Si alloy under the effect of directional solidification in ceramic mold chilled with copper. From the coupling between experimental (microstructure evaluation) and numerical (solidification simulation) study, a model is obtained. This model can be used to predict the microstruc...

This research work studied the fatigue behavior of as-cast acicular ductile iron produced by addition of Ni and Mo in conjunction with controlled cooling. Rotating bending fatigue-testing method of cantilever type at a stress ratio of R = -1 was employed. Crack growth rates da/dN were determined and plotted vs. crack length. It was shown that da/dN...