Cement foaming agent, also known as foaming concrete foaming agent, refers to an admixture that can reduce the surface tension of liquid and generate a large amount of uniform and stable foam for the production of foamed concrete. Foaming agent is a kind of substance that can make its aqueous...
Tial3 – An Intermetallic Compound
An intermetallic compound formed from Ti and Al atoms. It forms in a reaction-controlled process at both Ti/tial3 and Al/tial3 interfaces, as evidenced by X-ray diffraction and microscopic observations (SEM and OM).
Formation of tial3 is facilitated by its negative Gibbs energy - i.e., lower than that of a pure metal - which makes it easier to form than other high-aluminum phases, such as
Upon annealing, a tri-modal grain structure was observed in the intermetallic layer between the Ti and Al sheets. The grain structure consists of fine, nearly nano-sized tial3 nuclei/grains near the Ti/tial3 and Al/tial3 boundaries respectively. The grains at the centre portion of the intermetallic layer appear to be larger than those at the boundary areas, implying grain growth.
Given the faster diffusivity of Al compared to that of Ti, it is expected that huge mass transport of atoms occurs from the Al side to the Ti side during the diffusion process, which ensures a net growth of tial3 grains at the boundary areas, especially at the regions A and C indicated by red and blue dots in Fig. 6c respectively. This is confirmed by the arrows pointing towards these regions in Fig. 3b, which represents the shifting direction of the newly grown tial3 grains.
