"2007-09-26+02:00"^^ . . "C\u00EDlem projektu je vyvinout a pou\u017E\u00EDvat metodu neutronov\u00E9 difrakce s vysok\u00FDm rozli\u0161en\u00EDm pro in situ zkoum\u00E1n\u00ED martenzitick\u00FDch transformac\u00ED ve slitin\u00E1ch s tvarovou pam\u011Bt\u00ED (SMA). Tyto slitiny vykazuj\u00ED jedine\u010Dn\u00E9 termomechanick\u00E9 vlastnosti (tvarov\u00E1 pam\u011B\u0165, superelasticita, tlumen\u00ED mechanick\u00FDch vibrac\u00ED) odvozen\u00E9 od termoelastick\u00E9 martenzitick\u00E9 transformace v pevn\u00E9 f\u00E1zi. Pr\u016Fb\u011Bh transformace a s n\u00EDm i fyzik\u00E1ln\u00ED vlastnosti pam\u011B\u0165ov\u00E9 slitiny lze \u0159\u00EDdit teplotou a nap\u011Bt\u00EDm. D\u00EDky t\u00E9to schopnosti konat po\u017Eadovanou funkci se pam\u011B\u0165ov\u00E9 slitiny staly v\u00FDznamnou sou\u010D\u00E1st\u00ED modern\u00EDch adaptivn\u00EDch struktur a kompozit\u016F. Pomoc\u00ED metod in-situ neutronov\u00E9 difrakce lze nedestruktivn\u011B z\u00EDsk\u00E1vat informaci o frak\u010Dn\u00EDch pod\u00EDlech transformuj\u00EDc\u00EDch se f\u00E1z\u00ED, elastick\u00FDch m\u0159\u00ED\u017Eov\u00FDch deformac\u00EDch a zbytkov\u00FDch pnut\u00EDch uvnit\u0159 vzorku. Tyto \u00FAdaje umo\u017E\u0148uj\u00ED nal\u00E9zt vztah mezi mikrostrukturn\u00EDmi zm\u011Bnami v prvku z pam\u011B\u0165ov\u00E9 slitiny (zabudovan\u00E9m v adaptivn\u00EDm kompozitu) k makroskopick\u00E9 odezv\u011B SMA (kompozitu) p\u0159i termomechanick\u00E9 z\u00E1t\u011B\u017Ei." . "IAA1048107" . "29"^^ . " diffraction evaluation of stress" . "29"^^ . "Studium martenzitick\u00FDch f\u00E1zov\u00FDch transformac\u00ED v pam\u011B\u0165ov\u00FDch slitin\u00E1ch a kompozitech metodou neutronov\u00E9 difrakce" . "http://www.isvav.cz/projectDetail.do?rowId=IAA1048107"^^ . . . . "Byly vyvinuty nov\u00E9 metody in-situ neutronov\u00E9 difrakce ke studiu martenzitick\u00FDch f\u00E1zov\u00FDch transformac\u00ED v materi\u00E1lech a tvarovou pam\u011Bt\u00ED a modern\u00EDch ocel\u00EDch. V\u00FDsledky pomohly l\u00E9pe porozum\u011Bt a modelovat termomechanick\u00E9 funk\u010Dn\u00ED chov\u00E1n\u00ED t\u011Bchto materi\u00E1l\u016F."@cs . . . " shape memory alloys" . "neutron diffraction; diffraction evaluation of stress; shape memory alloys; phase transformations; martensite; thermomechanical loading; smart materials"@en . "1"^^ . . . . . . . . " thermomechanical loading" . "0"^^ . . . . . "This project is aimed at the development of in-situ high resolution neutron diffraction techniques to investigate martensitic transformations in shape memory alloys (SMA). SMA' exhibit unique thermomechanical responses (large reversible deformation, superelasticity, excellent dumping of mechanical vibrations) associated with the thermoelastic martensitic transformation controlled by external temperature or applied stress. The unique functional properties of SMA have recently found new range of engineering applications as actuating elements in smart structures and composites. The in-situ neutron diffraction techniques to be developed are expected to provide nondestructive bulk information on fractions of transforming phases, elastic lattice strains and internal stresses during the thermomechanical load cycle and relate thus the microstructural changes in the transforming SMA element to its macroscopic response. This is presently possible only through the mechanics modelling."@en . "2"^^ . . . "Neutron diffraction investigations of martensitic phase transformations in shape memory alloys and composites"@en . " martensite" . "neutron diffraction" . "New in-situ neutron diffraction methods for application to martensitic phase transformations in shape memory alloys and modern steels were developed. The results helped to comprehend and model the unique functional behaviors of these materials."@en . " phase transformations" . . .