Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Abstract The strain amplitude-independent and strain amplitude-dependent components of the internal friction in a Ni 45 Mn 36.7 In 13.3 Co 5 metamagnetic shape memory alloy have been studied as function of temperature, strain amplitude... more
Abstract The strain amplitude-independent and strain amplitude-dependent components of the internal friction in a Ni 45 Mn 36.7 In 13.3 Co 5 metamagnetic shape memory alloy have been studied as function of temperature, strain amplitude and polarizing magnetic field. ...
ABSTRACT The effects of long-range atomic order and pinning of interfaces on anelastic properties of Cu-based martensite have been distinguished by means of studying strain amplitude dependences of internal friction and Young’s modulus... more
ABSTRACT The effects of long-range atomic order and pinning of interfaces on anelastic properties of Cu-based martensite have been distinguished by means of studying strain amplitude dependences of internal friction and Young’s modulus defect, assuming that low-and high-amplitude stages of the strain amplitude dependence correspond to the oscillations within and beyond pinning atmospheres.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
ABSTRACT A technique referred to as mechanomagnetic spectroscopy, which combines the resonant piezoelectric composite oscillator technique with measurements of the periodic stress-induced magnetization of ferromagnetic samples has been... more
ABSTRACT A technique referred to as mechanomagnetic spectroscopy, which combines the resonant piezoelectric composite oscillator technique with measurements of the periodic stress-induced magnetization of ferromagnetic samples has been applied to study the magnetoelastic coupling in Ni51.5Fe21.5Ga27 single crystals. The composition selected demonstrates a martensitic transformation from the high-temperature cubic phase to the tetragonal one well separated from the para-ferromagnetic transition, allowing studying the high-temperature parent phase in the ferromagnetic state. Measurements were performed at fixed temperatures and oscillatory strain amplitudes as a function of periodic polarizing field and as a function of temperature for fixed values of applied magnetic field and strain amplitude. It has been found that the reversible inverse magnetostriction changes its sign in the cubic phase for the 〈1 0 0〉 orientation, first close to the Curie temperature and then also over a certain range of temperatures below that. This anomaly is not present for the 〈1 1 1〉 orientation. A possible origin of these peculiarities is discussed under the localized magnetic moment assumption.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Martensite ageing effects have been studied in the beta_1' martensitic pbase of a Cu-10.5wt%Al-0.5wt%Be alloy, exhibiting pronounced stabilization of martensite, by means of calorimetric studies and acoustic measurements. The latter... more
Martensite ageing effects have been studied in the beta_1' martensitic pbase of a Cu-10.5wt%Al-0.5wt%Be alloy, exhibiting pronounced stabilization of martensite, by means of calorimetric studies and acoustic measurements. The latter were performed in the range of non-liner anelasticity for temperatures between 300 and 9 K and allowed one to investigate variations of the mobility of linear/planar defects of martensite (partial dislocations, intervariant boundaries) for different heat treatments and ageing times in the martensite state. The conclusion is drawn that martensite ageing includes homogeneous and heterogeneous components. The former occurs in the bulk of a sample, whereas the latter is localized in the vicinity of lattice defects such as intervariant boundaries and/or partial dislocations limiting stacking faults.
Research Interests:
Non-linear anelasticity of several Cu-based beta_1 ' martensitic alloys, exhibiting different stabilization properties, has been studied over wide temperature (8 to 300 K) and strain amplitude (2*10^{-7} to 2*10^{-4}) ranges.... more
Non-linear anelasticity of several Cu-based beta_1 ' martensitic alloys, exhibiting different stabilization properties, has been studied over wide temperature (8 to 300 K) and strain amplitude (2*10^{-7} to 2*10^{-4}) ranges. Temperature ranges of quenched-in defect mobility were found to be similar for stabilizing Cu-Zn-A1 and for Cu-A1-Ni alloy, which is not prone to the stabilization, but different for two stabilizing alloys (Cu-A1-Be and Cu-Zn-A1). On the other hand, the interaction modes of quenched-in defects with linear/planar lattice defects differ significantly for Cu-A1-Ni and Cu-Zn-A1 alloys.