| Glass ceramic was used in the chemical industry because of their good chemical properties which depended on the composition of basic glass,crystal phase,residual glassy phase,the structure,laboratory conditions,and environment.In the dissertation,the acid durability of different glass-ceramics were investigated by DSC,XRD,FE-SEM,rotating crucible viscometer.Firstly,the acid resistant properties of Li2O-Al2O3-SiO2 glass ceramic,MgO-Al2O3-SiO2 glass ceramic and CaO-MgO-Al2O3-SiO2 glass ceramic were compared.The results suggested that the CaO-MgO-Al2O3-SiO2 glass ceramic showed weak durability and decomposed gradually in acid solutions,but the Li2O-Al2O3-SiO2 glass ceramic and MgO-Al2O3-SiO2 glass ceramic were very resistant to the action of acid,nearly insoluble.Secondly,the effect of Li2O?Na2O?K2O and Fe2O3 on the crystallization behavior and chemical durability of MgO-Al2O3-SiO2 glass and its glass-ceramic were studied.The results showed that in the same composition,glass ceramics with fine and uniform crystal were resistant when the crystallization temperature was1000?or 1100?,the difference of the surface morphology between before and after corrosion was small.With the increasing of crystallization temperature,especially at1200?,a severely decrease in the weight losses occurs in all samples as the main crystalline phase is cordierite which was dissolved easily by acid solution.At the same crystallization temperature,the weight loss of the samples containing Li2O was larger,the samples containing K2O had better acid resistance.The effect of the type and concentration of corrosion solutions seems not marked.The acid durability of basic glass with Fe2O3 was decreased,after nucleation and crystallization the acid durability improved.Samples containing 1%Fe2O3 had a relatively poor acid resistance.The samples crystallization at 1000?and1100?more durable than that crystallization above 1100?.with the increasing of crystallization temperature,the acid resistance decreased gradually. |
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