Mechanical Behaviour of Pure Aluminum Processed by Constrained Groove Pressing

Severe Plastic Deformation (SPD) process is capable of developing the submicron grain structures in metallic alloys and to improve the Mechanical properties. Constrained groove pressing is a processing method in which a metal is subjected to an intense plastic deformation through repeated dominant shearing and pressing (flatting) of plate. This method comprises bending of straight billet with corrugated tools and the restoring the straight shape of the slab with flat tools. The repetition of the process is required to obtain a large strain and desired structural changes. The Constrained Groove Pressing (CGP) processes are widely used in industries to compensate the high strength metal plates components used in automobiles. In the present work an attempt has been made to study the influence of CGP parameters like strain rate and number of passes to predict the degree of importance on grain size, micro hardness and tensile strength of CGP specimens. The results indicated that the number of passes has a major influence on the fine-grain refinement followed by strain rate

Optimization of the buckling parameters for e-glass/epoxy sandwich structure using taguchi approach

The objective of the paper was to investigate influence of buckling test parameters on buckling strength and deformation of e-glass /epoxy sandwich structures using statistical model like Taguchi technique. Three types of epoxy based corrugation i.e. sinusoidal, square and triangle of different core thickness and different strain rate were tested. This research work developed a multiple regression model for correlation between parameters and responses using L9 array. Analysis of variance was used to meas ure weightage of process parameters. Analysis of the influences of the entire individual input impact parameters on the responses has been carried out and significant contribution of parameters is determined by analysis of variance

Experimental And Numerical Analysis Of Propagation Of Stress Wave in Sheet Metal

In this experiment on the propagation of stress waves on sheet metal of different material andtheir effect of casing is studied and reported. Steel and aluminum are the two different types of materials which are considered and instrumented with the strain gauges. Metal foil gauges are most commonly used to measure the strain accurately. It is then externally impacted by the ball pane. The output that is obtained is in the wave form and is stored in the oscilloscope. The stress waves are induced in sheet metal, due to the impact of ball pane. The amplitudes of stress waves which are obtained from the oscilloscope, are studied and to determine the velocity of stress wave propagation and damping capacity of the material. Propagation of stress waves are obtained from the experimental and numerical methods are then compared it with the analytical methods

Effect of taper and twisted blade in Steam Turbines

Turbo machinery is critical to various processes and their application range from steam turbines to aircraft turbines. Turbo machinery bladed disks are subjected to severe centrifugal loads.The centrifugal force is one of the problems that face the designers of blades especially the long ones. The severe loading leads to large peak stresses. One way to tackle this is by using twisted blades or using variable cross-section area blades. Rotating structures having the shape of pre-twisted blades commonly affect the modal characteristics. In order to design the rotating structures properly, their modal characteristics must be estimated accurately. The modal characteristics of rotating structures often vary significantly due to the effect of the centrifugal inertia force induced by the rotation motion. For this reason, the modal characteristics of rotating structures have to be investigated. In this paper effect of taper and twist in steam turbine blade is analyzed using A NSYS. Blades are idealized as tapered cantilever beams that are fixed to a rotating disc.The results obtained are then utilized in the design of the constant stress blad

Statistical Investigation of effect of parameters on low velocity impact of fiber reinforced plastic corrugated sandwich structure

Fiber-reinforced plastic corrugated core sandwich panels were tested for low velocity impact using drop test method. Three types of epoxy based corrugation i.e sinusoidal, square and triangle of different core thickness and height of the drop were tested. The paper focused to development of statistical equations using multiple regression analysis, correlating various process parameters to responses such impact load, energy and deflection of the impacts. The experiments were conducted based on three factors and three levels (full factorial). The model adequacy was checked by Analysis of variance (ANOVA). The main effect and interaction effects of the impact parameters on responses were studied using contour plots. The correlation was obtained by multiple-variable linear regression using Minitab14 software. Analysis of the influences of the entire individual input impact parameters on the responses has been carried out and significant contribution of parameters is determined by analysis of variance (ANOVA)

Effect of Severe plastic deformation on Mechanical properties of Al6061/SiC Metal matrix composites

The severe plastic deformation process is capable of developing the submicron grain structures in metallic alloys and to improve the mechanical properties. Al6061/SiC composites become one of the most widely used composite materials in the engineering applications. Their light weight, low cost and considerable strength have favored their use in automotive and aerospace industries. In this paper the evaluation of Micro hardness, Ultimate Tensile Strength and ductile properties of severely plastic deformed specimens are discussed. This article describes repetitive corrugation and straighteni ng processes with Cyclic Constrained Groove Pressing parameters such as Wt. % of Sic, strain rate, Number of passes, Thickness of the specimen and heat treatment process. The results indicated that the percentage of Sic factor has a major influence on the hardness of the composite plate, followed by no. of passes, Heat treatment, plate thickness and strain rate. The optimal conditions for tensile strength are Wt.% of Sic of 15%, strain rate of 1.5mm/min, Number of passes of 7, specimen thickness of 4mm and heat treatment of 3hrs.Experimental results indicate that number of passes and Wt.% of Sic are most influencing parameters and other parameters are less significant

Study of Cyclic Constrained Groove Pressing Factors on Hardness Behavior of Al/Sic - MMC Subjected to Severe Plastic Deformation

Cyclic constrained groove pressing (CCGP) are widely used for the production of an ultra finegrained, Nano/sub microcrystalline structure in industries to compensate the high strength metal plates components used in automobiles. The present paper focus on The mechanical properties in nanostructure Al/Sic composite plate processed by a new technique, cyclic constrained groove pressing (CCGP), were studied using micro hardness tester. Taguchi technique and the analysis of variance (ANOVA) techniques were carried out to investigate the degree of importance of CCGP process parameters i.e. Percentage of Sic, strain rate, number of passes, plate thickness and heat treatment for four different levels. The results indicated that the percentage of Sic factor has a major influence on the hardness of the composite plate, followed by no. of passes, Heat treatment, plate thickness and strain rate. The Taguchi method and the ANOVA technique was an effective tool to predict the degree of importance of the CCGP parameters on micro hardness CGP specimens

Comparison of Riveted Panel and Integral Panel for Damage Tolerance by using FEA

Damage tolerance capability refers to the load carrying capacity of a damaged structure. In an aircraft metallic structure damage is the fatigue crack. The presence of a fatigue crack reduce the load carrying capacity of a structure. Damage tolerance design ensures that a structural component, in the presence of a fatigue crack, continue to possess the required load carrying capacity. Here the role of the type of the structural joints (riveted and integral) on damage tolerance quality of a structural component will be studied

Characterization of mechanical properties of aluminum processed by repetitive corrugation and straightening process using Taguchi analysis

The severe plastic deformation process is capable of developing the submicron grain structures in metallic alloys and to improve the mechanical properties. Repetitive corrugation and straightening (RCS) processes are widely used in industries to compensate the high-strength metal plates components used in automobiles. In this work, an attempt has been made to study the influence of RCS parameters like strain rate, number of passes, and plate thickness to produce grain refinement in metallic alloys. Experiments were based on the Taguchi method and the analysis of variance (ANOVA) technique was an effective tool to predict the degree of importance of the RCS parameters on grain size, microhardness, and tensile strength of RCS specimens. The results indicated that the number of passes has a major influence on the fine-grain refinement, followed by Al plate thickness and strain rate. © 2012 The Author(s)

Experimental and Numerical Analysis of Elasto-Plastic Behaviour of Notched Specimen to Tensile and Compressive Cyclic Loading

The objective of the work was to estimate the elasto-plastic stress and strain behaviour at the root of the notch of an Al 6061 plate undergoing tensile and compressive cyclic loading by both experimental and numerical methods. This attempt to measured initial elasto-plastic stresses experimentally then verified by numerically. The various Kt values such as 2, 4 and 6 specimens were subjected to tensile test using a computerised universal testing machine. Numerical approach associated with body discretization and developed finite element model with sufficient degree of freedom to analyses elasto-plastic analysis of notched specimen. Experimental results show that analysis of three Kt notched specimens had similar behaviour of elasto-plastic behaviour but different magnitude. The experimental results compare well with the numerical results which are obtained during finite element analysis of notched specimen