Search

The time-averaged flow characteristics in the regions upstream and downstream of the side-by-side cylinders of diameter ratio two, arranged at different longitudinal alignments and two gap ratios, are studied via particle image velocimetry (PIV). It is found that the locations of forward stagnation point of the large and the small cylinders do change with the longitudinal alignments. Upstream of the large cylinder, the streamwise variations of U* are nearly independent of the longitudinal alignment for both T*=1.5 and 1.0. However, upstream of the small cylinder, the streamwise variations of U* indeed depend on T*. Upstream of the small cylinder, the streamwise variations of V* are strongly affected by T* and, the largest magnitude of V* occurs at CLA for both T*=1.5 and T*=1.0. Also, the locations of the largest magnitude of V* move closer to the small cylinder as the T* reduces. For different T* and L*, the flow rate (or the averaged velocity through the gap) and the gap orientation will be changed at the same Reynolds number (Re=1000). The effect of pressure difference across the gap may be overwhelmed or be counterbalanced by that of the gap orientation leading to quite different flow structures in the downstream region of the cylinder couples. The effects of longitudinal alignment are to (1) change the forward stagnation points of the large and the small cylinders; (2) modify the region of mutual interaction between two wakes. (3) As S* reduces, the gap orientation takes the dominance over the pressure difference across the gap to switch the gap flow so that the wide-wake is formed behind the small cylinder especially for T*=1.0 and TEA.

The original development and use of Self-Compacting Concrete (SCC) in Japan started from the problem of the durability of concrete. Indeed, the reduction in the number of skilled workers, and the consequent poor compaction of structures, was a topic of great concern in the eighties, and helped the introduction of SCC. More recently, SCC is being commonly used in solid concrete slab in residential buildings for its excellent flowability. Additionally, to reduce structural self-weight without excessively affecting the slab thickness (which could represent a major issue in this applications), lightweight concrete represents a preferable solution. In this type of structure the development of anchorage or lap length becomes crucial, thus requiring a proper understanding of the bond mechanism. The result of an experimental campaign to assess bond properties for Lightweight Self-Compacting Concrete (LWSCC) are presented in this paper. The main investigated parameter is the bar size (ranging from 8 to 24mm) while the cover to diameter ratio and the bonded length to diameter ratio were kept constant. The experimental results are finally compared with code predictions.

B4C/Al composite was a promising neutron absorb material. In this work, B4C/Al composite sheets were asymmetrically rolled and annealed. The asymmetric (ASR) condition was introduced by applying mismatched roll diameters with diameter ratios of 1.1, 1.2 and 1.3, respectively., while the symmetric rolling (SR) was used as the control experiment. Mechanical properties and microstructures of the composite were tested after cold rolling and annealing. Results showed that: ASR with small diameter ratio decreased the texture volume fraction in the B4C/Al composite, but when diameter ratio of ASR reached 1.3 new slip systems were actuated and the texture volume fraction started to increase. The average grain size of the aluminium matrix was smaller after ASR, and it decreased with the increasing diameter ratio. The hardness of B4C/Al composite after ASR was about 40% higher than the one rolled by symmetric rolling, proved that ASR is a promising way to enhance the properties of B4C/Al composite.

Penetration efficiency reflects high speed projectile penetration ability with the impact velocity (>800m/s) variation. To further study the penetration efficiency engineering model, the physical and mechanical parameters that affect the penetration efficiency of high-speed projectiles penetrating into concrete target are analyzed, penetration efficiency dimensionless quantities are determined, such as projectile’s length to diameter ratio, projectile and target strength ratio, etc. The dimensionless equation of penetration efficiency is got by using the homogeneous principles of the laws of physics dimensionless. According to experimental data, a function of dimensionless penetration efficiency and dimensionless projectile speed is fitted. Finally, the model is verified by test, and the model calculations and experiment results agree well. The model obtained in this paper can estimate the projectile’s impact velocity when the penetration efficiency reaches the maximum, it would be a theoretical guidance for high speed penetration effects experiments.

In order to study the bearing capacity of unimate cross-section pipe pile and setp cross-section pipe pile, a finite difference model of the pile-soil interaction is established by FLAC3D,. The bearing behaviors of the setp cross-section pipe pile and the traditional unimate cross-section pipe pile are studied comparatively, the bearing performance influence factors of setp cross-section pipe pile is discussed. The results show that setp cross-section pipe pile can decreased the settlement relative to unimate cross-section pipe pile.There is an optimum diameter ratio in theory. For a reasonable pipe diameter ratio to setp cross-section pipe pile, on the one hand, it can effectively improve the stress behaviors of pile and reduces the pile settlement.On the other hand, it also can reduce the dosage of pile material and has good economic benefits.Under the action of the determinate pile load, the increase in length can reduce the settlement,but there is an optimal pile length, by increasing pile length to reduce the settlement of piles has little effect when the pile length exceeds the optimal length of pile.

In order to analyze the effect of RDX-based thermobaric explosive on strain rate, the stress-strain curves with different strain rates were measured by using the Split Hopkinson Pressure Bar (SHPB) and resistive strain testing technology. The different strain rates were obtained by changing the length to diameter ratio (L/D=0.46~0.92) and speed of the bullet (10~18m/s). The results showed that it is obvious to change the strain rate by the change of the L/D and speed of the bullet with different functional relationship; RDX-based thermobaric explosives have the evident strain rate: failure stress and strain are increased with the increase of strain rate.

A laser drilling technique named the nested-circle method is introduced in this work, in the respect of short-pulse laser processing.it is found that, as the power increases, the depth to diameter ratio of the hole will increase and the minimum number of circles can be set drilled hole reliably is reduced. Further studies have been carried out on the effect of the number of circles in the nested-circle method. Keys of settings the nested-circle method parameters—Outer circle diameter ‘D1’, Inner circle diameter ‘D2’, The Number of circles ‘R’—have been found out.

This issue deals with peculiarities of stress-strain state forming in a representative volume of inhomogeneous soil. Analytic solutions for describing such stress states and obtaining equivalent mechanical values for such massive are given. Basing on the performed triaxial laboratory tests the impact of diameter ratio, percentage, and contact between particles on mechanical properties of a mixture is estimated. As a conclusion some recommendations on using the research results in practical geotechnical engineering are given. The classification of inhomogeneous soils, based on granulometric data, allowing to estimate mechanical properties is presented, as a method of granulometric composition, humidity and density selection for artificial foundations.

Using melamine and aluminum nitrate as raw material, we prepared aluminum nitride whiskers by precursor method and studied the effect of reactants and concentration to AlN precursor. The results showed that when the Molar ratio is 1:3, and the concentration is 0.2mol/l, whisker precursor produced is relatively uniform and have large length diameter ratio.

Granular particles exist widely in the nature. The purpose of this paper is to research the impact interaction between rigid body and particles. The diameter ratio between rigid body and particle has the effect on the impact strength exerted on the rigid body impacting particles. In this paper, the same rigid body impacts respectively the particles with five different diameters. The effect of the diameter ratio is analyzed theoretically according to this simulation experiment. With diameter ratio increasing, the vertical velocity, mechanical energy and momentum of the rigid body increase, and the force exerted on the rigid body decreases.

The vortex shedding from two circular cylinders of different diameters in a tandem arrangement is numerically investigated at a Reynolds number of 100 and 150. The studied Reynolds number based on the diameter of the downstream main cylinder. The diameter of the downstream main cylinder was kept constant, and the diameter ratio between the upstream control cylinder and the downstream one was varied from 0.1 to 1.0. The gap between the control cylinder and the main cylinder ranged from 0.1 to 4.0 times the diameter of the main cylinder. It is concluded that the gap ratio and the diameter ratio between the two cylinders have important effects on vortex shedding from two cylinders of different diameters in a tandem arrangement.

Flow characteristics of two different diameters cylinders in a tandem arrangement were investigated numerically in a uniform flow. The diameter of the downstream main cylinder was kept constant, and the diameter ratio between the upstream control cylinder and the downstream one was varied from 0.1 to 1.0. The studied Reynolds number based on the diameter of the downstream main cylinder were 100 and 150. The gap between the control cylinder and the main cylinder ranged from 0.1 to 4.0 times the diameter of the main cylinder. It is concluded that the gap ratio and the diameter ratio between the two cylinders have important effects on the lift coefficients and pressure distribution.

The vertical single-phase flow was studied on the shell side of a horizontal tube bundle. In the present study, CFX version 14.0 from ANSYS was used to predict the flow regimes in the two tube bundles; i.e. the 19 mm and 38 mm arranged in an in-line configuration with a pitch to diameter ratio of 1.32. The simulations were undertaken to inform on how the fluid flowed within the tube passages in different tube bundle diameter that gives different gaps between the tubes, where the fluid must pass. The results show that the maximum gaps between the tubes have no clear effect to the flow where the flow separation and re-attachment and the average velocity is the same when increasing the tube bundle. This is consistent with other published data.

We demonstrate that single crystalline ZnO nanowires with large length/diameter ratio are successfully grown on Si, glass, and Si with ZnO seed layer via simple thermal vapor deposition, without introducing any catalyst or additive. In this work, we study impact of growth conditions such as growth temperature, substrates, and ZnO seed layer on morphology and photoluminescence properties of ZnO nanowires, in terms of systematic characterizations. The investigations show that the growth temperatures have substantial effect on the morphology of ZnO nanowires, while substrates have low impact. And 700 °C is believed to be the optimized growth temperature among the series of temperatures. Moreover, ZnO seed layer plays an important role in the uniformity and reproducibility of ZnO nanowires growth. PL measurements for the ZnO nanowires exhibit two emission bands including a UV emission and a blue emission, respectively. Finally, the growth behavior of the ZnO nanowires is discussed based on the VS growth mechanism. Our resluts have made a positive progress toward improving control of the morphology of ZnO nanowires.

Given the influence of carton black's morphology on rubber's property, A new method was supplied that the parameters, such as length diameter ratio, morphology complexity, were used to characterize carton black's morphology. Convex hull of carton black’s region was used to calculate morphology complexity. Minimum bounding rectangle of carton black’s region based on convex hull was used to calculate length diameter ratio. The quantitative evaluation of carton black’s morphology is meaningful for researching the relationship between carton black’s morphology and rubber’s property.

In the experiment of cavitation, the same water tunnel with different model size will get cavity shape that is different from the result of the empirical formula under the same cavitation number. In this article, we studied the impact of wall effect on natural cavity shape and the resistance of cavitator. We get the cavity shape and resistance of cavitator under different diameter ratio. We also get the law how cavity shape and resistance of cavitator change with the diameter ratio. The results provide a reference for experiment in water tunnel and the simulation model.

The dynamic simulation analysis method is adopted to investigate the dynamic damping characteristics of lathe tool with large length to diameter (L/D) ratio. The multi flexible body dynamical simulation model of dynamical damping lathe tool with large length to diameter ratio is built up according to the actual experiment lathe by using the software ADAMS and ANSYS. Simulation analysis of the multi flexible body dynamical model which has been optimized shows that the system damping performance is improved greatly. On this basis the relationship of rubber bush, mass body and vibration absorption cavity is discussed. And the result of the discussion indicates that the shape of rubber bush should be confirmed by repeatedly simulating the model.

In the dense phase pneumatic conveying lab table, used horizontal shrinked pipeline as transmission pipe. Used compressed air as conveying power and dry gypsum powder as transported materials, then conducted with gas-solid conveying experiment. Through the experiment, resulted show change law and influence factors of pressure drop in horizontal shrinked pipeline under different transportation conditions.In this study. The results showed that diameter ratio, solid and gas mass ratio and diffusion angle could affect the pressure drop of the pipeline .

The effect of physical scaling on one dimensional (1-D) conducting polypyrrole (Ppy) nanowire device has been successfully studied. The synthesis, electrical characterization and ammonia gas sensing with 1-D Ppy nanowire device have been carried out in the present investigation. Ppy nanowires having ~80 to ~200 nm in diameter were synthesized by electrochemical polymerization in alumina template and 1.77 to 3 µm Ppy nanowire length were maintain by varying the distance between electrodes gap. We further demonstrated that gas sensors based on 1-D Ppy nanowire having high aspect ratio (length to diameter ratio, L:D) exhibits good sensitivity towards ammonia, and provided a reliable detection at concentration as low as approximately 1 ppm based on principal of physical scaling co-related to response resistance.

The method adopted to manufacture copper clad steel wire in this study is cladding and welding and then drawing and annealing it. The effect of drawing deformation and annealing treatment on the grain size of α-Fe phase were studied. Experimental results show that the grain sizeα in cross section of α-Fe phase is decreased with the increase of the drawing deformation. Grains of the longitudinal section are elongated toward the drawing direction and appeared a strip shape. The grain size in cross-section of α-Fe phase is enhanced with the increase of the annealing time and annealing temperature, its length diameter ratio in longitudinal section is decreased oppositely. The grain size in cross section and length diameter ratio in longitudinal section are almost invariant in 850 °C for 2 h, the grain in longitudinal section tends to be equiaxial, the recrystallization processes is thus finished at this moment. Through the experimental data analysis, the regression equation about the relation of annealing temperature and annealing time of CCS with the grain size in cross section and length diameter ratio in longitudinal section are obtained.

In order to explore the blasting effect with charged by different length/diameter ratio in rock, adopted ultra-dynamic strain testing system to test the blasting strain wave with charged by little amount of explosives and different length/diameter in the rock models. Analyzed the radial blasting strain wave signal in the medium under the conditions of coupling charging explosive loading, got the generalities and difference of the explosive strain waveform features with charged by different length/diameter ratio, and relationship of peak strain with the relative distance. The results show that peak strain was greatly affected by the change of length/diameter ratio and charge mass in the area of close blasting source, when the relative distance is more than 45, the influence is less. Made the length/diameter ratio is 20 to be the boundary, when the length/diameter ratio is greater than 20, the peak strain attenuated slowly. The explosive energy of the big length/diameter ratio is relatively decentralized to the medium, improved the energy utilization ratio of explosives. The measured results provided a new experimental basis to further understand correctly the rock blasting mechanism.

This study investigated the mechanical properties of High Strength Concrete filled steel tubular short columns (HSCFSTSC) with length to diameter ratio (L/D) of 3.5.The strength of concrete used to fill the steel tubular columns ranged from 54MPa to 116MPa. The test results showed that using a steel tube as confinement can significantly improve the ductility and compressive strength of core concrete. The magnitude of compressive strength increase of core concrete was directly proportional to the Confinement Index, , and the extent of improvement of the ductility increases as the  increases. For thoroughly improving the ductility of core concrete, the Confinement Index  should be equal or larger than 0.48. The formula used to calculate the load bearing capacity of HSCFSTSC was given out.

Hadfield steel is wear-resisting steel and widely used where the devices have high impact wearing performance requirements. Cold asynchronous rolling technique can improve the mechanical performances of high manganese steel to a certain degree. Through experimental research, this paper studied the effect of deformation degree and diameter ratio on its mechanical performances during asynchronous rolling.

Through the analysis of stress in ultra high-pressure cylinders, found that its stress distribution is very uneven. In order to use the principle of autofrettage for improving design of the cylinders, first with Faupel-Furbe formula to calculate estimates of diameter ratio, and thus are inner and outer diameter of the cylinder block. Then the cylinder is determined parameter of autofrettage on the cylinder such as the optimum radius of elastic-plastic junction and the optimum autofrettage pressure. Finally, analysis and calculation of stress in improved design cylinder, the results show that the improved design of cylinder have a greater degree of improvement in weight, size and stress distribution of three areas. Key words: autofrettage; ultra-high pressure cylinders; diameter ratio; stress distribution.

Erosive burning usually refers to the increase in the propellant burning rate caused by high velocity combustion gasses flowing over the propellant surface. It may seriously affect the performance of solid-propellant rocket motors [1]. A series of experiments had been made to study the effects of length to the diameter ratio in a single tubular propellant grain on the erosive burning phenomenon. In the same combustion pressure and different grain geometries, the burning pattern of AP1based propellant were recorded. Furthermore, pressure-time curve for each condition was obtained. The mean velocity gradient is obtained by some thermo-gas-dynamical analysis on experimental data. The results can be used for preliminary design of AP based tubular propellant rocket motors. This method may be used for other types of tubular solid propellants which defer in chemical formulation.

In this paper an empty cylinder which is as a simulator for a ramjet engine has been studied by a cold flow. The air flow comes into the cylinder from one side and injection operation will be done by four nozzles which are located in the entrance of cylinder. By changing length to diameter ratio and injection angle, we have studied droplet sizing and efficient mass fraction of fuel vapor near and at the exit area. We named the mass of fuel vapor inside the flammability limit as the efficient mass fraction. To fulfill the calculation we used a modified version of KIVA-3V.

The preform of Al2O3 fiber was obtained by wet method,and the result shows that the fiber distribution of preform is more uniform after the pretreatment, and the length - diameter ratio can fully meet the demand of qualified preform. The surface of preform prepared by this process is flat, and fiber is distributed evenly, with certain strength,so it can be used for pressure infiltration fabrication of alumina fiber reinforced metal matrix composites.

The characteristics of stress distribution in high-pressure vessel are analyzed at first. Then the formula of inner pressure is derived. Through analysis the formula, a conclusion that the maximal inner pressure the high-pressure vessel can support goes steady under the diameter ratio is more than 5. Then the formula of equivalent stress at the dangerous position (inside wall) in high-pressure vessel is educed according to the fourth strength theorem and the quantitative relationship in the vessel’s inside pressure and diametrical ratio and the fatigue limit further is founded. Finally, the advice that proper structure is adopted to improve the cylinder’s inner pressure when design thick wall high-pressure cylinder according to relationships as above. These advices have a definite directive significance for how to design and use vessel effectively.

The multi flexible body dynamical simulation model of dynamical vibration absorption lathe tool with large length to diameter ratio is built up according to the actual experiment lathe tool by using the software ADAMS and ANSYS. The experiment data which are consistent with the simulation result verify the correctness of the multi flexible body dynamical model. Aiming at reducing the peak value of system frequency response, the dynamical vibration absorption system is optimized. The optimized frequency curve shows that the system frequency response is improved obviously. On this basis the influence of the mass of heavy turning body on the vibration system is discussed. Also, the relationship of the mass of heavy turning body and the optimal system parameters including equivalent stiffness coefficient and equivalent viscous damping coefficient is studied. This offers the design considerations about the structure of the dynamical vibration absorption lathe tool with large length to diameter ratio.

In this paper, the influence of geometrical parameters on failure load of bolted single-lap composite joint was investigated. The composite laminate was manufactured from HTA/6376, a high-strength carbon fiber–epoxy material currently used in primary structures in the European aircraft industry. Two geometrical parameters which were plate width-to-hole diameter ratio (W/D), and the edge-to-hole diameter ratio (E/D) were analyzed. To avoid modeling each ply of the laminates discretely, the laminates were modeled using equivalent linear elastic properties. the failure analysis was modeled by Extend Finite Element Method (XFEM) in ABAQUS. Maximum principal stress criterion (Maxps) was used to determine the failure load.

On the basis of analysis of aerodynamics characteristic of high length-to-diameter ratio missile on the fly, Study the stability of elastic vibration.

Plastic injection molding process is an advanced but much complex plastic part molding with multi-factors coupling interactive effects. The size of the part has a significant effect on the injection molding process. In the current work, a kind of common plastic part, common cup, is taken into study. Based on the 3D FE model, the effect laws of size of the common cup on the fill time, pressure at V/P switchover, clamp force needed and maximum deflection considering all effects in the injection molding process have been investigated. The research results show the following: (1) With increasing the initial diameter of the cup, fill time, pressure at V/P switchover and clamp force increase obviously, while overpacking happens for the maximum deflection considering all effects. (2) With increasing the initial height of the common cup, fill time, pressure at V/P switchover and clamp force increase less obvious. Meanwhile, overpacking doesn’t happen. (3) The effect of height to diameter ratio H0/D0 by changing D0 on injection molding process is different from that by changing H0.

Multi-way loading technology provides an efficient method to form integral triple valve parts. However, some forming defects such as cracking and folding are prone to occur, which will weaken the forming limit and quality of formed triple valves. Based on numerical simulation, taking forming load, damage, stress, strain and folding as objectives the forming limit and feasibility were studied by changing geometric dimension of billet and triple valve to be formed. The results showed that (1) for a given billet, as the inner diameter of triple valve increasing, the forming load, maximum damage value, stress and strain increased, i.e. the larger the inner diameter of triple valve the more difficult to form; (2) For triple valves with a given inner-outer diameter ration the maximum damage, maximum stress and strain values increased as triple valve outer diameter decreasing while forming load changed a little. The possibility of folding would augment with the increase of inner-outer diameter ratio d/D, when d/D≥0.8, folding occurred under the forming condition in this paper.

In this study AZ31 sheet with a thickness of 1.2mm and diameter of 52mm was simulated to press into a dish by a finite element method(FEM) software, which to obtain better processing of plastics forming of magnesium alloy by varying die parameters. In order to find the way of development on drawing property and to formulate the rational stamping processing, simulations have been applied on the maximum principal stress various with round radius of dent die and round radius of punch and die gap. Simulation results show that: to obtain a dish of 29mm diameter, a sheet of AZ31 magnesium with a thickness of 1.2mm and diameter of 52mm has been drawn, the fracture occurring at the corner of dish wall bottom. the ability of drawing varies with the round radius of dent die, which better radius is 3.8 mm. In the same way better round radius of punch is 3.0 mm, while better half gap is 1.8mm. Experiments also show that high diameter ratio has been increased with the various of die parameters and forming ability of material has been developed. It is reliable of simulation of finite element method.

The ordinary silk was puffed, the morphological structure of puffed silk was changed by testing, long diameter was shorter, short diameter was thicker, and the length to diameter ratio was changed. The properties of ordinary and puffed silk fabric were tested and compared, some performance of puffed silk fabric improved, means that the puffing treatment of Tussah silk is a useful way which can improve the performance of fabric and develop the silk product.

The question whether hidden weld of unstiffened overlapped CHS (circular hollow sections) KK-joints is welded or un-welded is not clearly mentioned in China's steel structure design codes (GB50017-2003) .This paper mainly analyzes the influence of chord-to-brace diameter ratio β, diameter-to- ply ratio γ and brace-to-chord ply ratio τ to the ultimate bearing capacity of the joints with the hidden weld welded and un-welded. The influence of welded and un-welded hidden welds of the joints on hysteretic behavior under low frequency loading is analyzed , and hysteretic curve of the joints are obtained by the finite element software ANSYS. Side brace or opposite brace of the hidden weld of the joints has little influence on the failure modes and ultimate capacity of the joints. Hysteretic behavior of the joints with the hidden weld un-welded is much better than that of the welded.

Sericite nanoflakes were prepared by exfoliating sericite layers by wet ultrafine grinding. Their appearance morphologies and main properties were characterized. Optimum conditions were studied with the purpose of forming shear stress which was beneficial to the exfoliation of mineral flakes. The results indicated that sericite nanoflakes could be prepared. Mass ratio of grinding media to materials, diameter ratio of grinding balls, solid content of powders and grinding time had significant effects on the preparation. The thicknesses of sericite nanoflakes were 20-80 nm, and the transmittances of ultraviolet ray with wavelength of 190-220 nm were only 0.1%-1%. This demonstrated that sericite nanoflakes had the function of shielding ultraviolet ray.

The paper studies machining technology, cutting parameter. It does experimentation research for drilling superfine deep-hole drilling of 2Cr13 stainless steel, of which slenderness ratio is greater than 300.The test result indicates that the drilling process is stable and reliable, the optimizing cutting technology and cutting parameters is rational, the production of the type of deep hole drilling technical problems have been solved. It has practical application in common production. The parameter can produce superfine deep holes of 2Cr13 stainless steel with the length to diameter ratio 322. In this paper, the key technologies of drilling 2Cr13 stainless steel deep hole are explained, which include selecting the system of drilling deep hole, designing of structure of deep hole bit, selecting the material of cutter blade of bit , and designing the geometry parameters of blade.

Pressure-Volume-Temperature (P-V-T) properties of two amorphous polymers (ABS and PS) were measured by an on-line testing measurement in the temperature ranges from 20 to 150 °C and pressures from 20 to 120 MPa. The on-line testing measurement is based on an injection molding machine (IMM), and it can be used to get P-V-T data of polymers directly with a special testing mold under normal processing conditions. The experimental P-V-T results of amorphous polymers under industrial processing conditions were presented. A new modified two-domain Spencer-Gilmore equation of state (EOS) was developed. The P-V-T properties were correlated by the modified Spencer-Gilmore EOS and a modified two-domain Tait EOS, showing a good agreement with measurements. The effects of sample forms were investigated. A sample with large length diameter ratio is the best one to be measured.

Aiming at the concentric shaft of the abnormal cross-section where there are two types of the concave fillet and the convex fillet and whose diameter ratio is bigger than 2, a 3D finite element computing model was constructed, and the stress and the strain is computed by means of software ANSYS8.0, and a stress concentration coefficient graph is found through comparing the result computed by FEM and by the method of material mechanics. It is concluded that the most important factors effecting the stress concentration are the type and radius of the transition fillet.

The interest in bulk nanostructured materials (NSM), processed by methods of severe plastic deformation (SPD), is justified by their unique physical and mechanical properties. Equalchannel angular pressing (ECAP) is one of the methods of severe plastic deformation (SPD) that produces ultra fine-grained material. Due to the cyclic nature of the process, it is difficult to produce specimens with a high length to diameter ratio. Ratios of 6-7 have been reported in the literature to date. Longer specimens, however, are useful since the homogenous part is larger and the relative size of end effects is smaller. A new method was developed to obtain length to diameter ratios as high as 8-10. This new technique was developed using the multi-pass finite element simulation. The as-received alloy used in this study was the 6082 commercial Al-Mg-Si alloy. High strength and high ductility phenomenon that was found recently in materials after SPD were reached with the route C. The induced anisotropy of specimens after ECAP was monitored.