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Advanced engineering materials 23(11), 2100111 (2021). doi:10.1002/adem.202100111, Herein, synchrotron-generated high-energy X-ray is used to study growthbehavior at the liquid���solid transition of multicomponent alloys during in situdirectional solidification experiments at Deutsche Elektronen-Synchrotron(DESY), Hamburg, Germany. The unique ���FlexiDS��� sample environment is usedto directly investigate crystal growth of a ternary eutectic Mo���17.5Si���8B alloy.During the directional solidification process, high-energy X-rays with a photonenergy of 100 keV (�� �� 0.124 ��) are used in transmission to obtain Debye���Scherrer diffraction rings. The diffraction rings were obtained within the liquidphase, the liquid���solid interphase and the solidified eutectic crystals by scanningthrough the respective observation volume of interest. The results provide strongevidences for a coupled ternary eutectic growth of the phases MoSS, Mo3Si, andMo5SiB2, which can be directly observed during in situ experiments for the firsttime., Published by Deutsche Gesellschaft fu��r Materialkunde, Frankfurt, M.

We have investigated the high-temperature solid-solution strengthening by oxygen in Nb, Nb-Ta and Nb-Mo single crystals by compression tests with constant strain rate. Nb, Nb-20Ta, Nb-40Ta, Nb-20Mo, and Nb-40Mo single crystals with various O content were grown by use of the electron-beam floating zone melting method. It is found that Nb and Nb-Ta single crystals are strengthened by oxygen at temperatures below 1100 K, while Nb-20Mo single crystals are strengthened even at 1473 K. The critical resolved shear stress (c.r.s.s.) of Nb-Ta single crystals at 298 K increases linearly with increasing O content, irrespective of Ta content. Furthermore, the increment of c.r.s.s. of Nb-Ta single crystals is larger than that of Nb. The c.r.s.s. of Nb-Mo single crystals is higher than that of Nb for all temperatures tested, and the c.r.s.s. of Nb-20Mo single crystals also increases with increasing O content. These results indicate that the interstitial-substitutional (i-s) interaction between O and Ta or Mo affects the mechanical properties in the Nb-based alloys at high temperature.

The technique to measure recrystallization texture for h.c.p. system by the SACP method is studied theoretically. In addition a SACP standard map covering the entire [0001–1210–1100] triangle is constructed in pure titanium. Based on the map the technique is examined experimentally and good agreement between pole figures measured with the SACP method and X-ray diffraction method is obtained. Es wird die Technik der Rekristallisationstexturmessung fur das h.c.p.-System mit der SACP-Methode theoretisch untersucht. Zusatzlich wird eine SACP-Standardkarte, die das gesamte 0001–1210–11001-Dreieck in reinem Titan uberdeckt, konstruiert. Auf der Grundlage dieser Karte wird die Technik experimentell uberpruft und es wird gute ubereinstimmung zwischen den Polfiguren erhalten, die mit der SACP- und der Rontgenbeugungsmethode gemessen werden.