Effect of Ti Addition on the Residual Aluminium Content and Mechanical Properties of the B4C-Al Composites Produced by Vacuum Infiltration / Wp?yw Dodatku Tytanu Na Resztkow? Zawarto?? Aluminium I W?a?ciwo?ci Mechaniczne Kompozytów B4C-Al Wytworzonych Przez Infiltracj? Pró?niow?

摘要

The effect of Ti addition on the residual Al content and mechanical properties of B4C-Al composites fabricated by vacuum infiltration was investigated in the present study. The B4C-Al composite materials were fabricated using [Ti+B4C] preforms preheated at 1700oC for 1 h and Al alloys infiltrated in vacuum atmosphere at 1100oC for 2 h. The phase composition indicated that TiB2 has high wettability to Al as a result of the preheating. SEM and EDX results revealed a number of Al dimples are on the fracture surface due to the existence of TiB2. When the content of added Ti increases to 30%, the [Ti+B4C] preform is characterized by a minimal porosity (33.11%) and a maximal density, a corresponding amount of residual Al of 33.11% and a minimal fracture toughness (5.03 MPa·m1/2) with a hardness of up to 63 HRC. The residual Al and the mechanical properties of the composite material preform were determined by the Ti content of the preform.