| Steel slag is a kind of byproduct during steel-making. With the development of the iron and steel industry, the quantities of the steel slag become more and more and engross a mass of ground, so it is very essential to deal with the steel slag. The steel slag is a kind of industrial waste residue during steel-making by high temperature melting, its melting temperature is higher than the burning temperature of the cement clinker about 1600℃. Because of so high temperature, the mineral is integrate crystallization growth,structure compact and crystallization bulky, so the mineral capability descends, and the steel slag need to be activated before it is dealt with. With the mechanochemitry advanced and gradually mature in theory, mechanochemistry is applied broadly among the practice, especially the development of the comminution mechanochemistry is more rapid, and the mechanochemistry effect can activate the potential capability of the materials. The process and effect of mechanochemistry is the changes of the physical chemistry property for the matter, mainly include the changes of the form,the structure and the physical chemistry property for the solid matter.One of the contents studied of this paper is the mechanochemistry changes of the steel slag and token it by a series of analysis and testing. The particle size is tested by the NSCK-1, and the testing results indicate the granule is diminished speedily during the initial stages of the comminution, when they are ground for period of time, the apparent granularity become wide for the agglomeration between them, with the more prolong of the grinding time, the particle size changes hardly and reach the grinding balance; The changes of the density for the steel slag powders are tested. The results indicate that with the prolong of the grinding time, because the crystal grain size incessant diminish and the amorphism on the surface of the grain, the amorphous layer become thicker gradually, and they lead to the density declining, but when the steel slag is ground for period time the density ascend because the agglomeration between them and the extrusion of the mechanical force; By XRD analysis, it mayobserve that the crystal degree fall, and show after the steel slag is ground by the planetary mill, the crystal structure is destroyed; By the SEM,TEM and HRTEM photos, they may observe the evident changes of the apparent shape,the particle size and crystal structure after the steel slag is ground by the planetary mill; By FI-IR analysis, it may make out that valence bond vibration become more violently even broken in a measure; It may observe the changes of the calorifics property to analyze DSC-TG curve, the result indicate its reaction degree increase after the steel slag is ground by the planetary mill, namely make the reaction go along easily.The other contents studied of this paper is the cementitious properties experiments and discuss the mechanochemical effects of the steel slag ground influence the capability of the steel slag. Compare the steel slag ground by the planetary mill with the steel slag un-ground by the planetary mill, after the steel slag is ground, the every moment compressive strength have evident increasing. When the BS has been ground for 5 hours the compressive strength of the BS for 3 days,7 days and 28 days increase respective from 0.392MPa,5.88 MPa and 12.936 MPa to 23.177 MPa,23.814 MPa and 28.322 MPa. The LS has the similar law with the BS on the compressive strength. It shows the mechanochemical effects have a remarkable effect on the capability of the steel slag. But the mechanical force may activate the steel slag, the chemical measure can activate the steel slag. In this experiment, by adding quantitative Na2SiO3·9H2O and bringing to bear mechanical force to the steel slag, it may become conscious of that the every moment compressive strength have increasing. It shows the alkali can activate the steel slag. By having the little lumps experiments for the compounds between the steel slag and slag, it may fi...
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