PROCESS ANALYSES FOR DEVELOPING COST-EFFECTIVE PARTICULATE REINFORCED INORGANIC COMPOSITES  
         
Takao Choh
 
Department of Materials Processing Engineering
           
 
Abstract
 
 
  The mechanical properties of composites are extremely controlled by the structure and properties of the reinforcement / matrix interface. These controlling factors are affected by fabrication process including operation time and temperature and the kind of matrix or reinforcement. In this paper, for developing cost-effective particulate reinforced inorganic matrix composites, some fabrication processes were proposed. From this point of view, the incorporation process and the wettability for ceramic / aluminum systems were evaluated by the time required for the incorporation of the ceramic particles into the molten aluminum during melt stirring. The effects of alloying element on the incorporation time and properties of composite were also measured. As a new fabrication process, stable carbide particles such as TiC were in situ synthesized in the liquid aluminum by reaction between the Al-Ti alloy and SiC or Al4C3 particles. Reactive infiltration of solid powder blends with molten aluminum or magnesium has been investigated as a potential route for the synthesis of a particulate reinforced metal matrix composite as well as an Al2O3 matrix composite.
 
Keywords: composite, wettability, melt stirring method,
      particle dispersion, reactive infiltration,
      in situ reaction, exothermic reaction,
      molten metal, ceramic powder
 
                  Contents
 
Introduction
1. Incorporation Behavior of Ceramic Particles into the Molten Aluminum by Melt Stirring Process
1.1 Introduction                                                  
1.2 Experimental procedure
1.3 Results and discussion
  1.3.1 Dispersion of SiC and ZrC particles in the molten aluminum
(1) Incorporation behavior of SiC particles and definition of incorporation time
(2) Effects of alloying elements on incorporation time of SiC and ZrC
(3) Reaction between the particle and matrix at elevated temperature
  1.3.2 Dispersion of AlN particles in the molten aluminum
(1) Effects of alloying elements
(2) Properties of AlN particulate-reinforced aluminum composite
1.2 Conclusions
References
2 In Situ Aluminum Composite Fabricated by Reaction between Al4C3
  or SiC particles and Al-Ti Alloy
2.1 Introduction
2.2 Experimental procedure
2.3 Results and discussion
2.4 Conclusions
References
3 Synthesis of Boride and Nitride Ceramics in Molten Aluminum by
  Reactive Infiltration
3.1 Introduction
3.2 Experimental procedure
3.3 Results and discussion
3.3.4 Observation of microstructure
3.3.5 Infiltration process analysis
3.3.6 In situ reaction analysis by DTA
3.4 Conclusions
References
4. Synthesis of AlN / Al Alloy Composites by In Situ Reaction between Mg3N2 and Aluminum
4.5 Introduction
4.6 Experimental procedure
4.7 Results and discussion
4.3.8 Microstructure
4.3.9 Analysis of reaction
4.3.10 Adiabatic temperature
4,4 Conclusions
References
5. An In Situ TiB2 / Al Composite Fabricated from TiN, TiCxN1-x and Boron Powders by Reactive Infiltration of Molten Aluminum
5.6 Introduction
5.7 Experimental procedure
5.8 Results and discussion
5.9 Conclusions
References
6. An In Situ-formed Boride / Al Composites Fabricated from B4C and Metal Powders by Reactive Infiltration of Molten Aluminum
 6.1 Introduction
 6.2 Experimental procedure
6.3 Results and discussion
6.4 Conclusions
References
7. Fabrication of Particulate Reinforced Magnesium Composites by Spontaneous Infiltration
7.8 Introduction
7.9 Experimental procedure
7.10 Results and discussion
7.3.11 Spontaneous infiltration and microstructure
7.3.12 Infiltration-front temperature and infiltration velocity
7.4 Conclusions
References
8. Synthesis of Al2O3 Matrix Composites by Reactive Infiltration
8.9 Introduction
8.10 Experimental procedure
8.11 results and discussion
8.3.12 Effect of TiB2 blending on the infiltration kinetics and
 the structure of the composite
8.3.13 Differential thermal analysis (DTA) and adiabatic
 temperature