Fabrication of Al-Al₃Ti/Ti₃Al Functionally Graded Materials under a Centrifugal Force

Fabrication of Al-Al₃Ti functionally graded materials (FGMs) under the centrifugal force has recently attracted some attention. The controlled compositional gradient of the fabricated FGMs, the low cost of the process, and the good mold filling, are the main advantages of the centrifugal method (CM). Using the conventional CM techniques such as the centrifugal solid-particle method and centrifugal in-situ method, FGMs rings with gradually distributed properties could be achieved. As a more practical choice, the centrifugal mixed-powder method (CMPM) was recently proposed to obtain FGMs containing nano-particles selectively dispersed in the outer surface of the fabricated parts. However, if a control of the particles morphology, compound formulas or sizes, is desired, another CM technique is favored. As a development of CMPM, our novel reaction centrifugal mixed-powder method (RCMPM) has been presented. Using RCMPM, Al‑Al₃Ti/Ti₃Al FGMs with good surface properties and temperature controlled compositional gradient could be achieved. In this short review, this novel method will be discussed in detail and the effect of RCMPM processing temperature on the reinforcement particles morphology, size and distribution through the fabricated samples, will be reviewed.