3,514 research outputs found
Structural-scale levels of development of inelastic martensitic deformation during isothermal loading of submicrocrystalline titanium nickelide in premartensitic condition
The results are presented of an experimental investigation into the regularities and mechanisms of the development of thermoelastic martensitic transformation in submicrocrystalline alloy Ti49.4Ni50.6 with different ways of thermo-power actions using the methods of optical microscopy in situ and X-ray diffraction. The peculiarities of localization of martensite transformation at the meso- and macroscale levels in this alloy with submicrocrystalline structure are considered. Experimental data on the relay mechanism of propagation of the martensitic transformation are presented. The interrelation between the localization of the martensitic transformation on the meso-and macroscale levels and deformation behavior under isothermal loading alloy Ti49.4Ni50.6 in submicrocrystalline condition are shown and discussed
Structure-scale levels non-elastic martensite deformation under isothermal loading of submicrocristalline alloy Ti49,4Ni50,6 in pre-martensite state
Spall fracture general regularities and patterns of coarse-grained and submicrocristalline Ni-Al alloy exposed to nanosecond relativistic high-current electron beam
Effect of ultrasonic sufrace treatment on the structure and properties of polycrystalline and nanostructured titanium
The effects of ultrasonic surface treatment on the structural and phase-state of subsurface layers of polycrystalline and ultrafine-grained titanium are investigated. The changes in microhardness, mechanical properties, and regularities of microplastic deformation buildup are studied under static and cyclic loading. It is found that the characteristics of polycrystalline titanium suffer most from the ultrasonic treatment, while its influence on ultrafinegrained titanium is considerably weake
The application of an assisting gas plasma generator for low-temperature magnetron sputtering of Ti-C-Mo-S antifriction coatings on titanium alloys
The positive effect of assisting influence of high-density gas plasma formed by an independent plasma generator PINK on mechanical and tribological characteristics of Ti-C-Mo-S magnetron coating on titanium alloys at lowered to 350Β°Π‘ temperature of coating regardless of alloy structural condition was revealed by methods of calotest, nanorecognition, scratch testing and frictional material tests. The coating formed by means of a combined magnetron plasma method reduces titanium alloys friction coefficient in multiple times and increases wear resistance by two orders of magnitude. At the same time the mechanical properties of ultra-fine-grained titanium alloys obtained by nanostructuring do not deteriorate
Theoretical model for ultracold molecule formation via adaptive feedback control
We investigate pump-dump photoassociation of ultracold molecules with
amplitude- and phase-modulated femtosecond laser pulses. For this purpose a
perturbative model for the light-matter interaction is developed and combined
with a genetic algorithm for adaptive feedback control of the laser pulse
shapes. The model is applied to the formation of 85Rb2 molecules in a
magneto-optical trap. We find for optimized pulse shapes an improvement for the
formation of ground state molecules by more than a factor of 10 compared to
unshaped pulses at the same pump-dump delay time, and by 40% compared to
unshaped pulses at the respective optimal pump-dump delay time. Since our model
yields directly the spectral amplitudes and phases of the optimized pulses, the
results are directly applicable in pulse shaping experiments
The ATLAS magnet test facility at CERN
The magnet system for the ATLAS detector at CERN consists of a Barrel Toroid (BT), two End-Cap Toroids (ECT) and a Central Solenoid (CS). The overall dimensions of the system are 20 m in diameter by 26 m in length. Before underground installation all coils will be tested on surface in a magnet test facility which is under construction. Moreover two model coils are tested as well as subsystems. In this paper the design and construction of the test facility is presented. (3 refs)
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