Principles of Structure and Phase Composition Formation in Composite Master Alloys of the Al–Ti–B/B4c Systems Used for Aluminum Alloy Modification

Resumo

The principles of formation of structure and properties of materials produced by self-propagating hightemperature synthesis (SHS) from the Al–Ti–B/B₄C powder systems are identified. It is shown that the SHSmaterials produced from the Al–Ti–B powder systems consist of a TiAl intermetallic matrix with inclusions of titanium diboride particles. It is found out that an introduction of 1 wt.% of TiB₂ particles into the melt of the AD35 aluminum alloy allows reducing the grain size from 620 to 220 μm and gives rise to an increase in the ultimate tensile strength of as-cast specimens from 100 to 145 MPa and in the plasticity from 7 to 9%.