INRTU scientists suggest using silicon production waste (gas purification dust) for obtaining most widely used aluminum casting alloys - silumins and composite materials. The scientists carried out the research within the framework of INRTU and RUSAL joint project on the creation of high technological production of nanostructures based on carbon and silicon dioxide (SiO2) by enriching gas cleaning dust.
It should be noted that silumins are aluminum casting alloys containing from 4 to 22 percent silicon content.
Depending on the content of silicon the alloys may have different characteristics. For example, the more the content of silicon is, the more rigidity of alloy and less its plastic properties are. Today there is almost no branch of industry where aluminum alloys are not used. Dishes, spare parts for cars, ships and motorbikes, firearms cases and others are produced on the basis of silumin.
According to the research staff of Innovative and Technological Center of Physical and Engineering Institute Mikhail KUZMIN, currently great scientific and practical interest is placed to the study of the possibility of obtaining aluminum-silicon system alloys by direct reduction of silicon from its aluminum oxides. We should pay the particular attention to the possibility of obtaining of silumins from micro and nanoparticles of amorphous silica, produced from ore-thermal furnace gas cleaning system of silicon production as a source of silicon.
"By adding of finely dispersed particles of SiO2 into the aluminum melt under certain temperature range, you can initiate the process of their recovery to Si. Thus, within the alloy production process silicon waste, consisting of 80-90 percent of the particles of amorphous silica, is converted from waste into product.
We expect to obtain not only alloys but also aluminum-matrix composites by using micro- and nanoparticles of silicon dioxide. The main distinction of the alloys from the composites is that they combine dissimilar materials such as aluminum and silicon oxide. Therefore, there is no need to reduce silicon from its oxide by the production of composites.
The main targets of this research are as follows: to obtain eutectic and hypoeutectic silumins corresponding to the state standard and produce composite materials with a uniform distribution of particles in metal volume and thus with improved strength characteristics.
So, within the work on large-scale project with UC "RUSAL" as the result of the enrichment of dust waste of JSC "Silicon" nano dispersed silica particles will be obtained as well as promising methods for their application in the aluminum industry will be offered", - M. KUZMIN emphasized.
Theoretical part of research in this field has been already completed. Scientists have found a thermodynamic possibility of flowing processes, conducted a set of experiments that showed prospects of practical implementation of the method of producing composite materials and silumins by announced technique. Currently the technology is fulfilled in the University laboratories using muffle and induction furnaces. The scientists will study different options for adding dispersed silica particles into aluminum melt to develop the technology as well as evaluate the efficiency of its implementation under industrial conditions.
As it was previously reported, the specialists of Innovative and Technological Center of Physical and Engineering Institute have been carrying out research within the framework of joint project by Engineering and Technological Center of Joint Company RUSAL and INRTU, that won competition on the Russian Government Resolution 218 (cooperation of HEIs and enterprises).