The Effect of Heat Treatment on the Structure and Mechanical Properties of Nanocrystalline Cu–14Al–3Ni Alloy Subjected to High-Pressure Torsion

The effect of heat treatment on the microstructure, phase composition, mechanical properties, and microhardness of the shape-memory Сu–14 wt % Al–3 wt % Ni alloy prepared in the nanocrystalline state, which results from the severe plastic high-pressure torsion (HPT), is studied. Electron microscopy and X-ray diffraction analysis are used in combination with electrical resistivity measurements in order to obtain data on the peculiarities of thermoelastic martensitic transformations and decomposition in the HPT-processed alloy subjected to thermal actions.

Analysis of efficiency of functionally oriented composite coatings made of materials with thermoelastic martensitic transformations

The efficiency of multifunctional composite coatings consisting of an intermediate adhesive layer and a surface wear-resistant layer undergoing thermoelastic martensitic transformations (TMT) is discussed. Using the example of a propeller blade, it is shown that materials with TMT in the composition of the surface composition provide an effective response to external influences (an increase in the endurance limit in seawater by 30%, wear resistance by 3.0—3.2 times, cavitation resistance by 15—20 times as compared to the base) and adaptation to loading conditions, that contributes to an increase in the service life. Evaluation of the stress-strain state of a propeller with the composite coating Ni—TiNiZr—TiNiCo showed a decrease in stresses in the most dangerous zone and confirmed the expediency of using materials with TMF to improve reliability.

Эффект пластификации сплава Cu-14Al-4Ni с эффектом памяти формы при высокотемпературной изотермической осадке

Deformation according to the scheme of uniaxial compression (with simultaneous measurement of mechanical properties) in isothermal conditions at 700-800°C provides a significant grain structure refinement of the Сu-14 mas.%Al-4 mas.%Ni alloy. It is found that this leads to an increase in the plasticity of the alloy experiencing thermoelastic martensitic transformations and associated shape memory effects. The structure was studied using the methods of scanning and transmission electron microscopy and X-ray phase analysis.

Crystal Structure of Martensite and Orientation Relationships During Thermoelastic Martensitic Transformations in Ni-Mn-Based Alloys

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Microstructure and Thermoelastic Martensitic Transformations in Ni-Mn-Al Based Alloys

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