3-Dimensional Microstructural Evaluation of Wear-Induced Layer in Al–Al₃Ti Functionally Graded Materials by Serial Sectioning

Abstract

The wear behavior of AlAl 3 Ti functionally graded materials (FGMs) ring was investigated by 3-dimensional microstructural observations. The AlAl 3 Ti FGMs ring was cast which contained platelet-shaped Al 3 Ti particles. The plane normal of the particles was parallel to the radial direction of the ring. The wear resistance of the AlAl 3 Ti FGMs ring depended on the sliding direction of the wear tests because of the anisotropic distribution of the Al 3 Ti platelet particles. A wear-induced layer with a fine microstructure was formed just below the worn surface, and the formation behavior of the layer also depended on the sliding direction. However, the equivalent Hencky strain required to form the wearinduced layer was about 5, regardless of sliding direction. The anisotropy of the wear resistance in the AlAl 3 Ti FGMs ring and the formation behavior of the wear-induced layer were explained by the shear strain distribution on the worn surface.

Grain Refinement of Al₃Ti Dispersed Aluminum Matrix Composites by Reaction Centrifugal Mixed-Powder Method

“…It is known that the equilibrium shape of Al 3 Ti particles in Al-Ti alloy is platelet. 23,24) In our previous study, the aspect ratio, defined as the ratio of platelet thickness to diameter, of Al 3 Ti platelet in Al-5 mass%Ti alloy is found to be 0.08. 25) If the Al 3 Ti platelet within the Al-Ti alloy has a facet structure as shown in Fig.…”

Heterogeneous nucleation of α-Al primary crystal on L12modified Al2.7Ni0.3Ti phase

“…However, many of them have been contradicted. Among them, we believe that the Al 3 Ti particles in the refiners act as the centers of heterogeneous nucleation in the mechanism of grain refinement, [11][12][13][14] where Al 3 Ti has a low-symmetry tetragonal D0 22 structure and its lattice parameters are a = 0.3851 nm and c = 0.8608 nm, while the Al phase has an fcc structure with a = 0.4049 nm.…”

“…The parameter M is readily applicable to predicting the preferred orientation relationships between the solidified Al and Al 3 Ti. That is, favorable heterogeneous nucleation sites for casting could be predicted using the parameter M. On the other hand, it is known that the shape of Al 3 Ti particles in the Al-5 mass % Ti ingot is platelet-like 21,22) and the face of Al 3 Ti platelets is a (001) Al3Ti plane. [22][23][24] Therefore, the dominant face of Al 3 Ti platelets is not the best plane for heterogeneous nucleation, since it has the largest M value among the above orientation relationships.…”

Fragmentation behavior of Al3Ti particles in Al-Al3Ti composite deformed by friction stir processing

“…Meanwhile as one of the methods to study the plastic flow, an investigation on the movement behavior of solid-particles in composite has been proposed 7) . This method can evaluate the plastic flow in large area.…”

“…This method can evaluate the plastic flow in large area. In previous studies, parts of authors have investigated about the fragmentation behavior of Al 3 Ti platelet particles in Al-Al 3 Ti composites during sliding wear [7][8][9] . The Al-Al 3 Ti composite consists of Al 3 Ti platelet particles and -Al matrix.…”