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Showing 1 to 20 of 69 for “"work hardening"”.
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FEM of nanoindentation on micro- and nanocrystalline Ni: Analysis of factors affecting hardness and modulus values.
… effective modulus to yield stress Eeff/σ and the work hardening behavior. Two separate cases of work hardening rates were considered; one with no work hardening rate and other with a linear work hardening rate. Specifically, it is observed that pile up is large only when hf/hmax is close to one …
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Ageing and strengthening of cold-rolled Al-Mg(-Cu)-Si-Mn alloys: experimental analysis and modelling
… rolled alloys during ageing: solid solution, work hardening, recovery and precipitation. Microstructure analyses revealed the formation of undissolved particles consuming the small Si addition, which influences age hardening behaviour of the alloys. Tensile testing was performed to evaluate …
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Ensaios de extrusão de barras entre matrizes de perfil sigmoidal
… lead in order to determine their isotropy and work-hardening conditions. Strip-extrusion experiments were afterwards made with a sigmoidal die profile for the maximum reduction condition, and with a straight die profile with the sarne reduction and axial lenght. The resul ts were compare d with …
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Abrasive wear resistance of ruthenium aluminide intermetallic and ferritic steels containing a sigma intermetallic phase
… Five different grades of thermomechanically worked ferritic steels specimens were heat treated to produce different volume fractions of sigma phase. The mechanical properties of the specimens were investigated by compression testing and microhardness measurements. Abrasion testing was carried …
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A study of the microstructural and mechanical properties of novel spring steels.
This work is concerned with track spring components manufactured by Pandrol from a SiMn alloy in the quenched and tempered condition. For many years low to medium carbon based spring steel has been manufactured via an oil quench temper route producing components with suitable mechanical and …
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Abnormal Grain Growth of AA2195 Friction Stir Weld Nugget during Solution Heat Treatment
… the effect of annealing and plastic deformation (work hardening),temperature at which the weld is deformed (cold and hot processing) and also the PWSHT time. It was found that the initial temper does not significantly affect the as welded nugget microstructure. Results indicate AGG to be dominant …
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Cavitation erosion of materials
… an awe phase transition which results in a high work hardening rate and high strain to fracture, NiTi similarly undergoes a phase transformation which allows absorption of seven per cent reversible strain and also results in a high work hardening rate. The erosion resistance of nickel based …
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Co-deformation of an aluminum zinc alloy
… sensitivity, tensile tested to determine work hardening and the temperature sensitivity, wire drawn to study the effect of large plastic deformation and finally tension compression tested to determine internal stresses. The bulk properties of the two phases are well known allowing for a …
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Calculation of Notch Strains Under Multiaxial Nominal Loading
… at the stress concentrator and anisotropic work-hardening effects are then related to this yield surface using standard methods of plasticity.
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Development and preliminary numerical investigations of a dislocation density-based finite-strain rate-dependent elastoplasticity constitutive model
… an internal state variable is developed in this work. The relationship between dislocation-based phenomena and working hardening in face-centred cubic metals is well-researched, and the popular Kocks-Mecking model for average dislocation density evolution has been successfully implemented in …
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Effect of strain rates on tensile properties and fracture toughness determination of extruded Mg-Al-Zn alloys
… effect of strain rates on tensile properties and work hardening behaviour were evaluated for extruded Mg-Al-Zn alloys. Further, the fracture behaviour at different loading rates and the effect of temperature on fracture toughness of Mg-Al-Zn alloys were investigated. The extruded Mg-Al-Zn alloys …
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The microstructure and some phase transformation characteristics of the dual phase steel 3CR12
… control of alloy content and heat treatment. The work has demonstrated the influence of the addition of alloying elements (in particular nickel), and thermal history. The dual phase (ferrite plus martensite) nature of the steel has been identified and characterised by both optical and transmission …
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Structural Evolution in the Dynamic Plasticity of FCC Metals
… of dislocation plasticity, based on the seminal works of Taylor and Orowan. It then progresses on to discuss recent experimental and theoretical work on the understanding of slip as avalanche behaviour. Chapter 3 summarises traditional modelling approaches for instantaneous strength contributions …
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Effect of Variable Amplitude Loading on Fatigue Crack Growth Rate
… da/dN under various conditions. The majority of work reported has focused on constant amplitude (CA) loading and some for variable amplitude (VA) loading. The estimation of da/dN under VA loading is complex due to effect of several factors such as plasticity, crack tip blunting, residual …
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The development of abrasive-corrosive wear resistance of steels by microstructural control
… abrasion resistance through the high degree of work hardening it undergoes during abrasion and the high ultimate strength of the strained material. The lath martensitic steel has the necessary strength to toughness ratio for good abrasion resistance. A 20% degree of work hardening in conjunction …
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The Effect of Pre-strain and Strain Path Changes on Ductile Fracture
… deformed in a given direction to fracture. The work presented here employed laser drilled model materials to better understand the effect of pre-strains and strain path changes on void growth and linkage leading to fracture is studied. The experimental results show that increasing pre-strain …
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An investigation into the prediction of thermal and stress distributions set up during welding using finite-element analysis
… and stress distributions are set up in the workpiece. These thermal stresses are recognized as among the most important factors affecting the weldability of steels, producing distortion and cracking in weldments. This thesis examines the history and theory of the welding process, including …
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A photoelastic study of stress distribution in a spur gear tooth
… evidence to the common practice of case-hardening the gear teeth. Previously this was done according to the mechanical properties of the gear materials, but without any analytical basis. Gear stress is a very complicated problem which includes in general the static, dynamic and fatigue …
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The fatigue-crack growth and fracture characteristics of a precipitation-hardened semiaustenitic stainless steel
… was attributed to the different amounts of work-hardening which occurs in the material prior to failure in the two cases. The effects of the different stress ratios on fatigue-crack growth were studied. In addition, the capability of the residual-strength analysis to predict the effects of …
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