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Showing 1 to 16 of 16 for “"Precipitation Strengthening"”.
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Synergistic precipitation strengthening effect of copper and niobium in high strength steel weld metal
Includes bibliographical references (pages 155-163).
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The effect of microalloying on the morphology of austenite during hot working.
… austenite, the transformation of austenite and precipitation strengthening in C-Hn steel containing niobium, niobium plus vanadium, vanadium and vanadium plus nitrogen. The amounts of niobium and vanadium were varied across the stoichiometric ratio of H:C and H:N in order to investigate the …
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Bauschinger effect in Nb and V microalloyed line pipe steels
… to provide grain refinement, solid solution and precipitation strengthening. During the UOE forming of large diameter (more than 400 mm) welded pipes the strength drop from plate to pipe, as a result of reverse deformation (the Bauschinger effect), depends on steel grade, namely microalloying …
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The Effects of Applied Strain and Heat Treatment on the Properties of NiTi Wire During Shape Setting
… applied strain were observed. Following theory, precipitation rates of Ni-rich phases generally increased with increased temperature (up to a certain point), time and applied strain levels. Reaction rates to achieve a particular Af might be faster than expected if the sample is under strain …
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Microstructure Characterization of SUS444 Ferritic Stainless Steel
… observed in the unaged sample was due to the precipitation of fine Laves phases which pinned down the motion of dislocations. As deformation progressed the strength increased until a critical precipitate size, volume fraction and dislocation density before Laves phases begun to rapidly coarsen …
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Effect of microalloying on pearlite transformation of high carbon wire steels
… for the V+N alloy. Vanadium additions produced precipitation strengthening for all alloys and heat treatments, and additional precipitation strengthening with nitrogen and niobium additions was not apparent based on a Taleff regression analysis. Atom probe tomography of an industrially processed …
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Impedance spectroscopy response of aluminum-copper-silicon alloys
… the observed electrochemical behavior with the precipitation strengthening reactions which occur during age-hardening. These precipitation reactions govern the resultant microstructure and determine the mechanical behavior, electrochemical behavior and type of corrosion attack observed in …
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Effects of vanadium microalloying of 1080 steel on pearlite transformation kinetics and microstructural development
… of the V addition on hardness. V partitioning/precipitation was analyzed through atom probe tomography (APT). Isothermal heat treatments were conducted with a focus on achieving isothermal pearlite transformations at 550, 600, and 650 °C. Care was taken to minimize the temperature increase …
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Mechanical and Physical Properties in Additive Friction Stir Deposited Aluminum
… size caused by the AFSD process had little or no strengthening effect on the mechanical properties of either alloy. Instead, the as-deposited condition in both alloys were soft with good ductility due to the dissolution of the strengthening particles. After heat treatment, the elongation and …
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Simulation of creep in nickel based single crystal superalloys
… This is due to two factors: solid solution and precipitation strengthening of the gamma ([gamma]) and gamma prime ([gamma]') phases, and the elimination of grain boundaries. Creep of Nickel based single crystal Superalloys are caused by two primary mechanisms, dislocation creep and diffusion …
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Influence of the heat treatment procedure on the stress corrosion cracking behaviour of low pressure turbine blade material FV566
… toughness. Tempering replaces the solid solution strengthening of the dissolved carbon with precipitation strengthening by carbides. The final microstructure of the FV566 steel blades is referred to as tempered martensite. van Rooyen showed that for 12% chromium steel tempering at and above 600°C …
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Strength modelling of Al-Cu-Mg Type alloys
… <br/><br/>The model considers a simplified precipitation sequence which involves a pre-precipitate structure followed by S phase. This pre-precipitate structure is referred to as Cu-Mg co-clusters instead of GPB zones based on atom probe and TEM studies from collaborators and a review of the …
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Elevated temperature mechanical properties of line pipe steels
… and the dissolution of transition carbides. Precipitation of cementite, which is associated with low temperature tempering, was theorized to contribute to the relatively high temperature mechanical behavior. Strain assisted bainitic tempering caused a shift in the flow stress maximum to …
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Transformation and precipitation in vanadium treated steels
… and vanadium added together. Examining the precipitation strengthening in tempered martensite showed that in the absence of vanadium, martensite softened progressively with increasing temperature and time. Vanadium additions increased the hardness level during low temperature tempering and …
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Characterization and Mechanical Properties of Nanoscale Precipitates in Modified Al-Si-Cu Alloys Using Transmission Electron Microscopy and 3D Atom Probe Tomography.
… the porosity, solid solution hardening, and precipitation hardening are preferred. All experimental variables such as solidification condition, composition, and heat treatment are influence on the precipitation behavior; however, precipitation hardening is the most significant because excess …