5.1.4. CAC + Additive Manufacturing

A search with the keywords, calcium aluminate cement and Additive manufacturing (CAC + Additive manufacturing) in the Scopus database returned 10 results. The number of documents produced per year is presented in Figure 8d. This reveals almost zero production in the last 10 years.

P. Shakor, et al. [68] They discuss a methodology for replacing the typical powders currently used in 3D printing to make it possible to use printed samples in construction applications. They found that the highest compressive strength (14.68 MPa) is obtained for samples that were first cured in water and then oven dried for one hour at 40 ◦C, compared to samples that were cured without drying at 40 ◦C (4.81 MPa). Therefore, the post-processing technique has a significant and effective impact on the resistance of printed samples. P. Shakor, et al. [69] developed a mixture of CAC through a 150 µm sieve and OPC for the Z-Corporation 3D Printing Process (3DP). This cement mix was mixed, and the resulting compound powders were printed with a water-based binder using a Z-Corporation 3D printer. In addition, lithium carbonate was added to some samples to reduce the setting time of the cement mix. The maximum compressive strength of the cubic samples for cementitious 3DP was 8.26 MPa at the 170% saturation level for both the shell and the core. The minimum porosity obtained was 49.28% at the saturation level of 170% and 340% for the cover and the core, respectively.

V. Antonovich, et al. [70] carry out a review on the use of nano technologies in the manufacture of refractory concretes and some other cementitious materials, examining the influence of nanostructure formation on the bonding material on the properties of refractory concretes. In one case, investigations were carried out using two-component bonding materials (sodium silicate solution mixed with dicalcium silicate) and three-components (sodium silicate solution mixed with dicalcium silicate plus calcium aluminate cement). Cement refractory concretes with mullite aggregates, micro silica, and hybrid and simple deflocculant additives (Castament FS20 polycarboxylate ether and sodium tripolyphosphate) was studied, finding that the three-component bond material hardens as opposed to the two-component material, since one of the bonding components (combination of sodium silicate and dicalcium silicate solution) hardens very quickly and affects the hydration process of the other component, CAC. This has a powerful impact on the entire structure of the material. The application of nanotechnology in the manufacture of refractory concretes has increased the compressive strength three times, from 55 MPa to 165 MPa. CACs can be effectively used as an accelerator for PC hydration for the purpose of layered extrusion. Das, et al. [71] established that CAC mixed with a source of calcium sulfate could be a better alternative than using CAC alone.
