| The steel smelting waste slag represented by stainless steel slag?SSS?is an important part of the modern urban mineral resources.In the field of mineral resources development and utilization in mining engineering cities development and utilizationand,how to realize its comprehensive utilization is one of the important topics.As a kind of SSS,AOD?Argon-Oxygen decarbonizing furnace?slag contains a variety of toxic heavy metal elements with large accumulation,which makes it one of the most difficult slag for comprehensive utilization.Glass ceramics,a kind of multi-phases composite materials,possesses excellent abrasion and corrosion resistance performance,has been proved to be a promising treatment method of solidification of heavy metals.However,the influence of composition changes on glass ceramics physical properties,microstructure evolution has not been revealed.Glass ceramics was prepared by melting method in this paper,the effect of SSS contents and SiO2/MgO on glass ceramics melts thermophysical properties,structure and physicochemical properties were investigated in this paper by FTIR,DSC,XRD,SEM-EDX and other test methods.In order to promote the industrial production of stainless steel slag glass ceramics,an orthogonal experiment was operated to explore the optimum heat treatment and conclusions are as follows:With increasing SSS contents,the viscosity???of glass metls decreased,while the electrical conductivity???increased.The relationship can be described by ln?=?-?ln?with?fluctuating around 1.The crystallization activation energy varied within 335473 kJ/mol.The crystallization index n is about 1,revealing a one-dimensional crystal growth.With the flexural strength and density as the measurement indexes,the optimal amount of SSS was determined to be 60%,and the flexural strength and density of the glass ceramics were about 150MPa and 3.0g/cm3 respectively.The high-temperature melt viscosity and viscous activation energy decreases with SiO2/MgO decreased from 7.5 to 4.5.When SiO2/MgO=4.5,the crystallization index was3.21,with the highest crystallization capacity.The proportion of pyroxene and wollastonite were 63.07%and 22.03%,respectively.The bending strength,vickers hardness,coefficient of thermal expansion and density were 176.21Mpa,8.81GPa,10.97×10-6/?and 3.08g/cm3,respectively.By optimizing the process parameters of heat treatment of base glass,the influence factors of process parameters on the material's flexure strength was determined in order of:crystallization temperature,crystallization time,nucleation temperature and nucleation time.The optimal heat treatment was decided as 720?×1h and 800?×2h.The flexural strength,vickers hardness,density and corrosion resistance of the glass ceramics were up to 196.81MPa,9.66GPa,3.1g/cm3 and 90%respectively.The results can lay a theoretical foundation for the harmless treatment of the SSS and the comprehensive utilization of urban mineral resources. |
PDF Full Text Request