Recently, it has been found that mechanical alloying (MA) facilitates the nanocomposites formation of metal-metal oxide systems through solid-state reduction during ball milling. In this work, we studied the MA effect of FeO-M (M = Al, Ti) systems, where pure metals are used as reducing agents. It is found that composite powders in which O and TiO are dispersed in -Fe matrix with nano-sized grains are obtained by mechanical alloying of FeO with Al and Ti for 25 and 75 hours, respectively. It is suggested that the large negative heat associated with the chemical reduction of magnetite by aluminum is responsible for the shorter MA time for composite powder formation in FeO-Al system. X-ray diffraction results show that the reduction of magnetite by Al and Ti if a relatively simple reaction, involving one intermediate phase of FeAlO or FeTiO. The average grain size of -Fe in Fe-TiO composite powders is in the range of 30 nm. From magnetic measurement, we can also obtain indirect information about the details of the solid-state reduction process during MA.

W-Cu composite has been used for the applications requiring both high strength, good thermal and electrical conductivity. A graded combination of W and Cu will reduce thermal stress concerned with heat conduction, maintaining good thermal conductivity and high mechanical strength. In the present work, an attempt was made to fabricate continuous W-Cu FGM by preparing the graded porous structure of W skeleton using spark plasma sintering (SPS) process followed by infiltrating Cu. The graded porous structure was prepared at 150 for 60s under pressure of 15MPa by SPS process using a graphite mold with varying crr)ss section in the longitudinal direction. Infiltration of Cu was performed at 115 for 1 hour under . W-Cu composite with graded Cu composition of 14 to 27 wt％ was finally prepared. In this process the gradient of composition could be conveniently controlled by varying the gradient of cross sectional area of graphite mold, temperature and pressure.

In this study the possibility to obtain a homogeneous mixture and to produce solid solutions and intermetallic compounds of Fe and Al nano particles by simultaneous pulsed wire evaporation (S-PWE) have been investigated. The Fe and Al wires with 0.45 mm in diameter and 35 mm in length were continuously co-fed by a special mechanism to the explosion chamber and simultaneously exploded. The characteristics, e.g., phase composition, particle shape, and specific surface area of Fe-Al nano powders have been analyzed. The synthesized powders, beside for Al and -Fe, contain significant amount of a high-temperature phase of -Fe, Fe Al and traces of other intermetallics. The phase composition of powders could be changed over broad limits by varying initial explosion conditions, e.g. wire distance, input energy, for parallel wires of different metals. The yield of the nano powder is as large as 40 wt ％ and the powder may include up to 46 wt % FeAl as an intermetallic compound.