Dense (>95% of theoretical density) TiAl3-based composites reinforced with 10-50 vol. % of B4C or TiC and 10-30 vol.% of TiB2 particles were successfully prepared by pressureless reaction sintering. In the case of reactive systems (TiAl3-B4C and TiAl3-TiC), densification proceeds via formation of various secondary bonding phases, whilst in non-reactive system (TiAl3-TiB2) the process seems to proceed by infiltration of molten aluminium into pores. The superior room temperature tensile properties were observed in TiAl3-B4C and TiAl3-TiCsamples with 50 vol. % of ceramic particles.
COBISS.SI-ID: 22747943
TiAl and Ti3Al based composites reinforced with TiC particles were successfully prepared by pressureless reaction sintering. Densification was promoted by reactions between TiAl or Ti3Al and TiC leading to the formation of Al2Ti4C2 and Ti3AlC phases. The addition of Al and Ti promotes liquid reaction sintering and the formation of Ti-Al-C bonding phases. The tensile properties and Vickers hardness of composite samples were measured at room temperature. The improvement in tensile properties and Vickers hardness was found to correlate with the amount of TiC reinforcement in the matrix.
COBISS.SI-ID: 758442
Mg-Mg2Si-TiC composites with continuous magnesium matrix densified to >95 % T.D. were fabricated by pressureless reactive infiltration of performs made from Mg2Si and TiC powders. Mg2Si–TiC/TiB2 ceramic composites densified to >97 % T.D. were prepared by pressureless reactive sintering of tablets made from Mg2Si and TiC or TiB2 powders. The results have shown that Mg-Mg2Si-TiC composites are with tensile properties superior to that of conventional magnesium alloys while Mg2Si–TiC/TiB2 samples combined high hardness (9–10 GPa) and low density (2.2. –2.5 g/cm3).
COBISS.SI-ID: 23199015
The key development challenges include the production of composite components based on AlFe, TiAl and Mg reinforced with ceramic particles by reactive sintering; the production of the three-layer composites Al-Fe, Al-Ti and Al-Mg with a binding layer based on intermetallic alloys reinforced with ceramic particles; and the production of the composite components based on the intermetallic alloys Al-Mg-Ti with reactive infiltration. The key novelty of our approach is the reverse-flow infiltration, used as a procedure for producing macro-composites or multi-layer, ceramic-metal composites.
COBISS.SI-ID: 11593750
We studied the efficiency of using the intermetallic alloys Al-Ti and Al-Fe in the development of the microstructure and to improve the mechanical properties of the Al alloys. We found that the Al-Ti and Al-Fe inserts have a large influence on the growth of the Al grains, allowing the production of Al alloys with a more uniform and fine-grained microstructure, which also significantly improves the mechanical properties.
COBISS.SI-ID: 673962