Steel nanocomposite was obtained by quenching and the metallic glass obtained from a Fe-based alloy which followed by devitrifying the glass precursor through heat treatment above its crystallization temperature where it showed a crystalline multiphase microstructure. There are advantages and limitations of the mentioned methods, such as Fe-based nanocomposites prepared by solidification techniques. Spray pyrolysis liquid metal infiltration rapid solidification vapor techniques (PVD, CVD) electrodeposition and chemical methods are the most common techniques for the processing of metal matrix nanocomposites ( Baker et al., 2004 Yoon et al., 2002 Provenzano et al., 1992 Contreras et al., 2004 Bhattacharya & Chattopadhyay, 2001 Bhattacharya & Chattopadhyay, 2004 Srinivasan & Chattopadhyay, 2004 Branagan, 2000 Branagan & Tang, 2002 Xiaochun et al., 2004 Ying & Zhang, 2000 Choy, 2003 Joseph et al., 2005 Chow et al., 1990 Haubold & Gertsman, 1992 Holtzt & Provenzano, 1994 Cushing et al., 2004 West et al., 2003 Kamat et al., 2002 Carpenter et al., 2000 Chen et al., 2000 Chen, Wong, et al., 2002 Chen, Lee, et al., 2002 Chen, Zhang, et al., 2003 Chen, Lee, et al., 2003 Xu et al., 1999 Noguchi et al., 2004 Kuzumaki et al., 1998 Yang & Schaller, 2004). Faruk Hossen, in Silica and Clay Dispersed Polymer Nanocomposites, 2018 11.3.4 Metal matrix nanocomposites (MMNC) However, a combination of a 2 μm TiC layer applied to the Textron SCS6 fiber and an addition of 0.5 wt.% C to the alloy prevented dissolution of the SiC and good composite mechanical properties were reported. They found that even with processing times as low as 5 s the fibers suffered severe damage (see Figure 26). In subsequent work Warrier and Lin (1995) used their rapid IR heating method to produce Ti–6Al–4V/Textron SCS6 SiC fiber reinforced MMCs. Unfortunately, the low-temperature alloys used in these experiments are of limited commercial interest and conventional engineering titanium alloys all have melting temperatures in excess of 1700☌. Figure 27 shows a three-ply titanium–nickel alloy/Textron SCS6 SiC fiber composite made by the IR rapid heating liquid metal infiltration method. The authors report good fiber wetting, no void formation and reaction zone thicknesses and, in the case of titanium/SiC composites, mechanical properties comparable to conventional diffusion bonded titanium alloy/SiC fiber composites. Warrier and Lin (1993) used IR rapid heating to infiltrate titanium alloy/graphite fiber and titanium alloy/SiC fiber composites and claim liquid metal contact times of less than 30 s at 1250–1350☌ with an unspecified low melting point titanium–nickel based alloy. On the other hand, too high a fiber temperature results in long solidification time, and hence undesirable reactions occurring at the fiber/matrix interface are highly possible. If the fiber temperature is too low, the solidification may occur prior to complete infiltration, thereby resulting in porosity in the composite cast. However, a strong dependence on fiber temperature of infiltration necessitates control of the operating temperature. Another advantage over squeeze casting is that the pressures applied are greatly lower. The process has the advantage of producing complex shaped components with the possibility of rather high fiber volume fractions. The pressure is kept applied until solidification occurs. Both the die and the metal chamber are evacuated and subsequently the melt chamber is pressurized by an inert gas, for example, argon, which forces the molten metal into the die to infiltrate the fiber preform. This die is then closed, but is maintained open to a reservoir chamber of molten metal. A preheated preform is placed into a split metal die in the shape of the component. The difference is that the infiltration of preform of fibers or particles by liquid metal is provided by means of a pressurized inert gas and the process is operated under vacuum. Liquid metal infiltration (LMI) process 12,13 can be considered as another variant of squeeze casting. Bakkar, in Reference Module in Materials Science and Materials Engineering, 2016 3.1.2 Liquid metal infiltration
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