Why the compounds in cement and their crystalline forms matter

Portland cement is composed of silicates, aluminates, alkaline sulphates, and minor oxides such as free lime and periclase. X ray diffraction technique - XRD – has long been performed to analyze free lime to give a direction in the clinker production, focused on the energetic efficiency of the process and quality of the product. Nowadays the same technique can be used in the quantification of all clinker and cement phases present in the production process, making possible to rapidly predict physical and mechanical properties of the product.

XRD with Rietveld refinement for quantification is the fastest and most accurate way to quantify all clinker phases and polymorphs of alite, belite and C3A, which are directly correlated to strengths and setting time of a cement paste. In addition to quantifying clinker phases, the method makes possible the quantification of all cement phases such as gypsum, limestone and even amorphous additions – fly ash, slags and pozzolan.

The aim of this presentation is to show the importance of each compound that constitute the Portland cement and how to perform XRD quantitative analysis in a fast way in order to obtain information about the clinker and cement production process that can be predictive of properties and performance.