نتایج جستجو برای: isothermal annealing
تعداد نتایج: 40861 فیلتر نتایج به سال:
We present a new method for the determination of self-diffusivities in solids and corresponding activation energy diffusion using in-situ Neutron Reflectometry. In contrast to classical ex-situ approach based on sequence isothermal measurements at different temperatures, allows one work with single experiment ramping temperature constant rate. Our demonstrates success model system amorphous ger...
The age hardening process of a 6082 Al–Mg–Si alloy by isothermal ageing at 100, 125 and 150 °C for 0 to 40 days has been investigated by both conventional and high-resolution transmission electron microscopy. Changes in sizes and densities of the pre-β and β phases during ageing can explain the evolution of hardness, in particular a plateau in the curve of the hardness versus ageing time. Fully...
Article history: Received 5 December 2017 Received in revised form 22 January 2018 Accepted 23 January 2018 Available online xxxx Structural relaxation during isothermal annealing, quantified by enthalpy recovery of Zr44Ti11Cu10Ni10Be25 towards its metastable equilibrium and correlation to embrittlement, quantified through fracture toughness, KQ, is studied. Enthalpy relaxation over time obeys ...
In this Letter, direct experimental evidence is provided for understanding the thermal stability with respect to crystallization in the Zr(41.2)Ti(13.8)Cu(12.5)Ni(10)Be(22.5) glass-forming liquid. Through high-resolution transmission electron microscopy, the atomic-structure evolution in the glass-forming liquid during the isothermal annealing process is clearly revealed. In contrast with the e...
Simultaneous TG/DSC measurements performed on mixtures 2Li2CO3-5TiO2 (anatase) subjected to high-energy milling showed that both the temperature and the enthalpy of Li2CO3 decomposition are much lower than in the case of TG/DSC runs performed on a sample of a physical mixture. On the basis of the thermoanalytical evidence a solid-state synthesis of the spinel compound Li4Ti5O12 has been propose...
A bulk metallic glass forming alloy is subjected to shear flow in its supercooled state by compression of a short rod to produce a flat disk. The resulting material exhibits enhanced crystallization kinetics during isothermal annealing as reflected in the decrease of the crystallization time relative to the nondeformed case. The transition from quiescent to shear-accelerated crystallization is ...
Nucleic acid nanotechnology has enabled researchers to construct a wide range of multidimensional structures in vitro. Until recently, most DNA-based structures were assembled by thermal annealing using high magnesium concentrations and nonphysiological environments. Here, we describe a DNA self-assembly system that can be tuned to form a complex target structure isothermally at any prescribed ...
Semiconducti ng glasses used for electron multipli ers and micro channel plate devices are obtained by surf ace modi Ùcation of Pb or Bireach silicon -based glasses. T he reduced layer extends dow n to 200{500 nm, much more than the e ̃ective depth of the electronemittin g layer. By the use of slow-positron beam w e monitor the structural changes undergoing in neartosurf ace layers after isother...
Band contrast (BC) is a qualitative measure of electron back-scattered diffraction (EBSD), which is derived from the intensity of the Kikuchi bands. The BC is dependent upon several factors including scanning electron microscope measurement parameters, EBSD camera setup, and the specimen itself (lattice defect and grain orientation). In this study, the effective factors for BC variations and th...
Thermomigration experiments were conducted to study the change in mechanical properties of 95.5Sn–4Ag–0.5Cu (SAC405) lead-free solder joint under high temperature gradients. This paper presents some observations on samples that were subjected to 1000°C /cm thermal gradient (TG) for 286 h, 712 h, and 1156 h. It was observed that samples subjected to thermal gradient did not develop a Cu3Sn inter...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید