| Slag glass-ceramics material which is composed of uniform distribution glass phase and minicrystal phases, can be prepared by the parent slag glass via controlling the behavior of crystallization. As a kind of new inorganic material, it has many super properties such as higher mechanical strength, good grinded, corrosion, weathering heat resistant capacity, and adjusted expansion coefficient. So, it has been used in various fields widely as the functional and structural materials.In the paper,the major raw material of fly ash and nickel slag, adding limestone, quartz sand, pure alkali and other raw materials, were used to prepare the slag glass-ceramics by melting method.Basing on the the best batch and the best parameters of heat treatment,we mainly investigates the quotiety and quality of deoxidized iron during the course of parent glass preparing according to the characteristic of batch; meanwhile, we discussed the effects of different kinds and contents alkali metal oxid on the glass-ceramic properties,and technics parameters of prepareing the glass-ceramic composite tube by centrifugal molding are also researched originally.The results showed: taking the plumbago as reducing agent, the quotiety of deoxidized iron is about 70%—85% and the quality of deoxidized iron is also better,which contains two kinds of alloy-- Fe0.905Si0.095 and Fe7Ni3;The crystallized temperatures descended as the contents alkali metal oxid increased after the different kinds and contents alkali metal oxids were added in the batch ,and the capability of reduced crystallized temperatures by alkali metal oxids is Li2O, Na2O>K2O,Li2O>Na2O, K2O;the main crystalline phases also changed as the kinds and coutents of alkali metal oxids changed, though the main crystalline phases of glass-ceramics are augite and diopside, a few LiAlSi3O8 appeared when the countents of alkali metal oxids are 6% or 8% and the countents of nepheline will increase as the countent of Na2O increased;different samples coefficient of thermal expansion will changed between 12.22×10-6 1/K— 14.78×10-6 1/K due to the mixed alkali;when the total coutents of Li2O,Na2O is 8%, the glass and the glass-ceramic's coefficient of thermal expansion are separately 14.1×10-6 1/K,14.15×10-6 1/K between 200—500℃,which can match perfectly with the common steel's coefficient of thermal expansion .Comprehensive many facters such as: the coefficient of thermal expansion, mechanical properties, chemical properties ect, the batch of A2 was used to prepare the composite tube,and get the last molding parameters : rotational velocity 1200r/min, rotational time 7-8min, anneal temperature at 600℃ in 40-50min; right preheated temperature of steel tube is 400℃.By a series of properties' tests, the result showed that it is feasible to prepare glass-ceramic and glass-ceramic composite tube utilizing Ni-slag and fly ash whichwas more than 60%.The glass-ceramic has great social and economical beneficence because of well performance.
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