THE FORMATION OF TiAl3 DURING HEAT TREATMENT IN EXPLOSIVELY WELDED Ti-Al MULTILAYERS

Metallic-intermetallic laminate (MIL) composites are promising materials for structural applications especially in the aerospace industry. One of the interesting laminate composites is the Ti-TiAl 3 multilayer. In this work, commercially pure sheets of aluminum and titanium with almost equal thickness of around 0.5 mm were explosively joined. The achieved multilayers were annealed at 630 ℃in different times so that an intermetallic layer was formed at the Ti/Al interface. The resulting microstructure was studied by optical and scanning electron microscopy and Energy Dispersive Spectroscopy (EDS). TiAl3 was the only intermetallic phase that was observed in all annealing times. The kinetics of the formation of TiAl 3 was investigated and compared to previous research studies performed on Ti-Al multilayers which were fabricated using methods other than explosive welding

Evolution of texture in precision seamless tubes investigated by synchrotron and neutron radiation measurement

High precision dimensionality tubes are required for a number of applications. Nevertheless, there are sometroubles and challenges to produce high quality tubes in a cost-effective way. In recent works done at theInstitute of Metallurgy at Clausthal University of Technology, the tube drawing process was optimized by introducingdynamic tilting and shifting of the die. These methods made it possible to control the wall-thicknessvariation and even residual stresses (RSs) evolution. A possible influence on texture evolution, however, has notyet been investigated, though it is well known that the crystallographic texture has a remarkable effect onmaterials' properties. Furthermore, the initial texture clearly influences the microstructural evolution duringplastic deformation, affecting the RSs evolution and dimension accuracy, too. In this paper the evolution andheterogeneity of the texture are introduced for tube drawing performed with a tilted die. The measurementswere done using synchrotron and neutron diffraction methods. The aim was to understand the behavior of thematerial during the asymmetrical tube drawing, caused by the tilted die, and connect the effects between eccentricityand residual stresses. Pole figures and ODF densities were studied and the creation and variation ofdifferent texture components were analyzed as well