IMPROVING THE PROPERTIES OF ALLOY AL4 MELTED FROM CHARGES INCLUDING SECONDARY SILUMINS.

Over 30 grades of secondary silumin are produced from scrap and recycled materials in the USSR. Experience at the Minsk Engine Works and the Altai group of engine producers has shown that secondary silumins can be recycled as part of the charge used to melt alloy AL4. All the above foundries replace virgin silumins by a proportion (up to 20%) of secondary alloy AK9. The scope for using a wider range of secondary silumins in this way has been explored. The alloy AL4 melts were made in a 125 kg pouring furnace with a cast iron crucible. The melt composition was adjusted to correspond to the requirements of GOST left bracket All-Union State Standard right bracket 2685-75. Tensile testpieces conforming to GOST 2685-75 were poured in cast iron sample molds preheated to 200-210 degree C.