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Information × Registration Number 0212U001718, 0110U002562 , R & D reports Title Research of electrodynamic effect on gas saturation of the melt and pores formation in cast aluminum alloys popup.stage_title Head Sinchuk Alla Vadymyvna, Registration Date 02-03-2012 Organization Institute of Pulse Research and Engineering popup.description2 Purpose of paper is to determine engineering and technological ways to obtain cast porous alloys by electrodischarge effect on the melt. It is fixed by experiments that treatment of the melt surface by a corona discharge of a positive polarity during hardening in a temperature range from 700 оС to the solidus temperature allows for reaching the porosity volume that compensates for shrinkage of alloy АК7, but does not ensure homogeneous distribution of pores across the cast bulk. It is fixed by experiments that surface electrodischarge treatment of the crystallizing alloy on the contrary causes degassing of the melt. By passing the pulse current with a maximum amplitude from 4 to 7 kA at pulse frequency 12 Hz, in the commercial aluminium the volume of uniformly distributed porosity from 40 to 50% is yielded, in the alloy АК7 - from 10 to 20%. The character of gas inclusions in the melt during passing of current pulses in different directions is described. Fixing of a gas phase in metal with known values of dynamic viscosity and specific electroconductance is provided by electromagnetic forces forming a pressure gradient in a fluid conductor different from metal static pressure. Thus, the density of current pulse passing whose minimum quantity is calculated by the height of the cast and preset maximum size of the pores is a technological parameter that restricts spread of the gas inclusions on the melt surface. Product Description popup.authors Іванов А.В. Дьогтєв Ю.Н. Мельник О.В. Рубан Г.С. Тарасенко Р.О. Федченко Н.А. Харитонова Т.Г. Цуркін В.М. popup.nrat_date 2020-04-02 Close