Abstract: In the present study, high-content Ti3AlC2 ceramic powders were fabricated by mechanical
alloying (MA) using the Ti, Al and C as the starting materials. And the effect of Al content on the
formation of Ti3AlC2 was investigated. The results showed that the large-sized granules were obtained to
coexist with the powders after ball milling of 3Ti/Al/2C powder mixtures for 3 h. Ti3AlC2 in the
synthesized powders is the main phase based on the XRD analysis. For the composition of 3Ti/1.1Al/2C,
high-content Ti3AlC2 powders (87.6 wt.%) have been obtained after milling for 3h. Excessive Al,
however, would reduce the content of Ti3AlC2 in the products.
Abstract: The oxidation characteristics, composition profile and phase transition of Ti3SiC2 in the
temperature range 20-1400°C have been investigated by in-situ neutron diffraction and secondary ion
mass spectroscopy (SIMS). Anatase has been observed to form at ~600°C, rutile at ~750°C and
cristobalite at ∼1300°C. Depth-profiling results by SIMS and Vickers indentation have revealed a distinct
gradient in composition and microhardness within the surface oxide layers.
Abstract: Al/Ti3AlC2 composites containing 50vol% Al were prepared with high purity of polycrystalline
Ti3AlC2 and aluminum powders by pressureless-sintering route at temperatures of 700°C~ 800°C The
tribological properties of the composites were investigated by sliding the composites block dryly against
low carbon steel disk under high sliding speed. Before and after friction test, the morphology and phase
analysis were observed by scanning electron microscope (SEM) and X-ray diffraction (XRD), separately.
A definite tribo-glazing layer was found over the worn surface of the composite block, which was the
results of tribo-chemical oxidation reaction and the cause forming it could be the high frictional
temperature and the mechanical catabolism between the surface of Al/Ti3AlC2 and low carbon steel
during sliding friction. The effect of Ti3AlC2 on tribological properties of Al/Ti3AlC2 composite and the
possible tribo-chemical reaction mechanism on surface layer of Al/Ti3AlC2 were suggested.
Abstract: In this paper, we presented a novel route for fabricating Ti3SiC2-based and Ti3AlC2-based solid
solutions with mixed powders of TiC/Ti/Si/Al in different molar ratios. The phase compositions of these
solid solutions were studied by XRD and the stoichiometries of these compounds were determined to be
Ti2.63Si0.87Al0.13C2 and Ti2.76Al0.78Si0.22C2 by EDS. We also investigated the electronic properties and
mechanical properties of these two ceramics. The results showed that the dopants were not only beneficial
to the fabrication of Ti3SiC2 and Ti3AlC2 but also improved the properties of these two ceramics.
Abstract: In this study, free Ti/Si/Al/C powder mixtures with molar ratio of 3:0.4:0.8:1.8 were heated in
Argon with various schedules, in order to reveal the possibility for the synthesis of Ti3Si0.4Al0.8C1.8 solid
solution powder. X-ray diffraction (XRD) was used for the evaluation of phase identities of the powder
after different treatments. Scanning electron microscopy (SEM) was used to observe the morphology of
the Ti3Si0.4Al0.8C1.8 solid solution. XRD results showed that predominantly single phase samples of
Ti3Si0.4Al0.8C1.8 was prepared after heating at 1400oC for 5 min in Argon and the lattice parameters of
Ti3Si0.4Al0.8C1.8 lay between those of Ti3SiC2 and Ti3AlC2.
Abstract: The Cu/Ti3AlC2 composites were fabricated by pressureless sintering a mixture of Ti3AlC2 and
copper powders. Their microstructures and properties were investigated. It was found that the molten Cu
accelerating the decomposition of Ti3AlC2, inducing the interfacial exfoliation to generate, and forming a
sub-micro-layered structure making up of TiCx layers and Cu-Al alloy layers within a Ti3AlC2 grain. The
flexural strength of the composites is reduced with the increase of the volume content of Ti3AlC2 from
50 % to 90 %. The highest flexural strength reaches to as high as 915 MPa. The fracture mode was
changed from ductile to brittle with increase in the content of Ti3AlC2. The higher flexural strength can be
attributed to a stronger interface bond between TiCx and Cu-Al phase. The electrical resistivity and
Vickers hardness of the composites were also measured.
Abstract: Joining of Cu/Ti3AlC2 cermet by an argon-arc welding technique without filler was firstly
investigated. The results show that the Cu/Ti3AlC2 cermet can be joined firmly. The joining strength at
room temperature was measured to be 851 MPa after optimization of the welding parameters with 2.6
A/mm2 for arc current density, 5 s for arc time, 10.8 kPa for applied pressure and 12 V for arc voltage. The
microstructure in welded zone shows that fine TiCx particles uniformly dispersed in a network structure
of Cu-Al alloys. This feature endows the Cu/Ti3AlC2 cermet with the high joining strength.
Abstract: Ti2AlC/TiAl composites with the addition of niobium were prepared by spark plasma sintering
using titanium, aluminum, niobium elemental powers and TiC particles as reactants. The experimental
and analytical studies on this kind of material concentrated on the relationship between reinforcement
phase and mechanical properties. The Ti2AlC/TiAl composites with 5% niobium exhibit high mechanical
properties. The three-point bending strength and fracture toughness reaches as high as 915MPa and 23
MPa·m1/2, respectively. It is found that the in-situ reaction occurs at 1100°C with the addition of niobium
at the interface between the TiAl matrix and original reinforcement TiC. Further XRD results indicate
that the difference in the reinforcement phase from TiC to Ti2AlC is one of the most important origins to
the variation in mechanical properties.
Abstract: Homogeneous and transparent enstatite fibers were prepared via the sol-gel process of metal
alkoxide precursors. The gel-to-ceramic conversion was characterized. The solution compositions had a
significant influence on the microstructural evolution of gel fibers. Infrared studies indicated that
bidentate bridging ligands were formed between acetate and metal ions, which enhanced spinnability
remarkably. The as-drawn fibers were essentially microporous. On heating to 800 oC, enstatite ceramic
fibers exhibited mesoporous structures with nanocrystals in size. The optical transmittance of enstatite
ceramic fiber in the visible range was around 90 % after heating at 800 oC.
Abstract: Compared to traditional fiberglass, basalt fibers have a wide spectrum of applications used as
textile fiber or reinforcement for composites. Epoxy resin composites filled with basalt fibers were
prepared by proper curing, using KH-550 silane coupling agent to enhance the interfacial bonding
between the inorganic reinforcing agent and the polymer matrix. The milling abrasive wear was investigated
in slurry containing sand abrasive particles using milling equipment. The experimental results
indicated that basalt fibers, EP and the nano-sized SiO2 filling formed steady composites. The wear rate of
the sample was reduced with the increase of resin content before the content of resin amounted to 40%.
When the content of resin is more than 40%, the wear rate of the sample deceased slightly.