다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Physical metallurgy of Ti–Ni-based shape memory alloys

Data Reduction And Error Analysis For The Physical Sciences

Ni4Ti3-precipitation during aging of NiTi shape memory alloys and its influence on martensitic phase transformations

The family of oxide glasses is very wide and it is continuously developing. The rapid development of advanced and innovative glasses is under progress. Oxide glasses have a variety of applications in articles for daily use as well as in advanced technological fields such as X-ray protection, fibre glasses, optical instruments and lab glassware. Oxide glasses basically consist of network formers, such as borate, silicate, phosphate, borosilicate, borophosphate, and network modifiers such as alkali, alkaline earth and transition metals. In the present review article, Raman spectroscopy results for the structures of borate, silicate, phosphate, borosilicate, borophosphate, aluminosilicate, phosphosilicate, alumino-borosilicate and tellurite glasses are summarized.

A review of the structures of oxide glasses by Raman spectroscopy

Influence of rare earth oxide (Nd2O3, Er2O3) addition on structure and glass properties has been investigated in PbO–B2O3–Al2O3–WO3 system. With an increasing of rare earth concentration, intensity of OH band drastically decreases and IR transparency is slightly shifted to the longer wavelengths. The ErBO3 crystalline phase has been identified basing on X-ray diffraction analysis. In opposite to the neodymium oxide, the erbium oxide plays the role as glass-modifier and influences on BO3 ↔ BO4 conversion, what was stated by infrared spectroscopy.

Structure and properties of rare earth-doped lead borate glasses

Two-stage martensitic transformation in a deformed and annealed NiTi alloy

Structure and spectroscopy of rare earth – Doped lead phosphate glasses

Lead borate based glasses have been analyzed using Raman and infrared spectroscopy. The formation of different borate groups and the direction of BO3 ↔ BO4 conversion strongly depends on the PbO- and/or PbF2-to-B2O3 ratio in chemical composition. PbF2−PbO−B2O3 based glasses containing Er3+ ions have been studied after annealing. The orthorhombic PbF2 crystallites are formed during thermal treatment, which was evidenced by X-ray diffraction analysis. Near-infrared luminescence at 1530 nm and green up-conversion at 545 nm have been registered for samples before and after annealing. The luminescence bands correspond to 4I13/2−4I15/2 and 4S3/2−4I15/2 transitions of Er3+ ions, respectively. In comparison to the precursor glasses, the luminescence intensities are higher in the studied transparent oxyfluoride glass ceramics. Simultaneously, the half-width of the luminescence lines slightly decreases. It can be the evidence that a small amount of the Er3+ ions is incorporated into the orthorhombic PbF2 phase.

Er-doped lead borate glasses and transparent glass ceramics for near-infrared luminescence and up-conversion applications.

Shape-memory properties of equiatomic NiTi, Ni45Ti50Cu5, and Ni25Ti50Cu25 ribbons made by melt spinning have been studied by temperature inducing the martensitic transformation under constant tensile loads. Recoverable strains above 4 pct can be obtained under ∼100 MPa loads for the NiTi and Ni45Ti50Cu5 ribbons, transforming to B19’ martensite. The B19 martensite is formed in the Ni25Ti50Cu25 ribbon after crystallization, and according to the lowering in transformation strain as Cu content increases, the recoverable strain is close to 2.5 pct for ∼150 MPa load. The transformation temperatures exhibit a linear dependence on the applied stress, which can be quantitatively described by means of a Clausius-Clapeyron type equation. The NiTi and Ni45Ti50Cu5 ribbons exhibited some degree of two-way shape-memory effect (TWSME) after thermomechanical cycling. Texture analyses performed on the different ribbons allow us to better understand the transformation strains obtained in each ribbon. The amounts of shape-memory effect (SME) and nonrecoverable strain shown by the studied ribbons are of the same order as those already observed in bulk materials, which makes melt spinning an ideal substitute to complicated manufacturing processes if really thin samples are needed. However, applicable stresses in melt-spun ribbons are limited by a relatively “premature” brittle fracture caused by irregularities in ribbon thickness.

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Tomasz Goryczka

Papers

Structure and properties of rare earth-doped lead borate glasses

Two-stage martensitic transformation in a deformed and annealed NiTi alloy

Structure and spectroscopy of rare earth – Doped lead phosphate glasses

Er-doped lead borate glasses and transparent glass ceramics for near-infrared luminescence and up-conversion applications.

Shape memory properties of Ni-Ti based melt-spun ribbons