Wear behavior of Al-Al3Ti composite manufactured by a centrifugal method

Abstract

The purpose of the present study was to develop a wear-resistant, light Al-Al 3 Ti composite material. An Al-Al 3 Ti composite specimen was machined from a thick-walled tube of Al-Al 3 Ti functionally graded material (FGM) manufactured by the centrifugal method from a commercial ingot of Al-5 mass pct Ti master alloy. The alloy was heated to a temperature where solid Al 3 Ti particles resided in a liquid Al matrix, and then the centrifugal method was carried out. Al 3 Ti particles in a commercial alloy ingot exist as platelets, and this shape was maintained through the casting. Three kinds of wear specimens were prepared, taking into account the morphology of the Al 3 Ti particles in the thickwalled FGM tube; the Al 3 Ti particles were arranged with their platelet planes nearly normal to the radial direction as a result of the applied centrifugal force. The wear resistance of the Al-Al 3 Ti composite was significantly higher than that of pure Al. Wear-resistance anisotropy and dissolution of the Al 3 Ti into the Al matrix at the near-surface region, around 100 m in depth, were also observed. The mechanism of the supersaturated-layer formation and the origin of the anisotropic wear resistance are discussed.

Wear Properties of Intermetallic Compound Reinforced Functionally Graded Materials Fabricated by Centrifugal Solid-particle and In-Situ Methods

“…In this case, anisotropic wear resistance is observed, dependent on the wear direction with respect to the alignment of the Al 3 Ti platelet particles (8) . The orientation of the Al 3 Ti platelets, as well as the mean volume fraction of the particles, was found to be gradually distributed in the Al-Al 3 Ti FGM (9) .…”

“…Solid-Particle Method (17) Al-Al 3 Ti FGMs were fabricated using the centrifugal solid-particle method in a similar manner to that of previous studies (7)(8)(9)(10) . The master alloy ingot was a commercial aluminum alloy containing 5mass% Ti.…”

“…The first type is the centrifugal solid-particle method, in which the processing temperature is lower than the liquidus temperature of the master alloy, whereby the dispersed intermetallic particles are stable inside a liquid matrix (7)(8)(9)(10) . The other method is the centrifugal in-situ method (11)(12)(13)(14)(15)(16) , in which the processing is implemented under temperatures higher than the liquidus temperature of the master alloy.…”

“…As a result, in the case of the centrifugal in-situ method, the centrifugal force is applied to a completely liquid phase and the intermetallic compound particles crystallize from the liquid phase directly during the casting process. One product of the centrifugal solid-particle method is Al-Al 3 Ti FGM, which contains anisotropically oriented Al 3 Ti platelets in the Al matrix (7)(8)(9)(10) . Figure 1 shows a schematic representation of the arrangement of the Al 3 Ti platelets in an Al-Al 3 Ti FGM ring, which is the typical shape of the finished product fabricated by the centrifugal method.…”

Review Fabrication of Functionally Graded Materials under a Centrifugal Force

“…It is known that volume fraction, size, shape and orientation of reinforcements in composite play an important role in improving the mechanical properties of the materials. Therefore, the Al/Al 3 Ti FGMs with oriented Al 3 Ti platelets should have an anisotropic wear resistance (Watanabe et al, 1999). The anisotropic wear resistances in the Al/Al 3 Ti FGMs were measured in three directions, namely along the longitudinal direction on outer surface of the ring (A), along the radial direction on the radial plane (B), and along the hoop direction on the radial plane (C), and results are shown in Fig.…”