Method of joining carbon-carbon composite pieces together, e.g. in the refurbishment of aircraft brake discs. The method includes the steps of: providing a first carbon-carbon composite piece and a second carbon-carbon composite piece, wherein the second carbon-carbon composite piece has a surface that is complementary to a surface of said first carbon-carbon composite piece; providing a layer of a mixture of titanium powder and carbon powder on the first complementary mating surface; arranging the second carbon-carbon composite piece on the powder layer such that the second complementary mating surface is matched to the first complementary mating surface, thereby forming a construct of the first carbon-carbon composite piece, the powder layer, and the second carbon-carbon composite piece; placing the construct into a press and applying pressure to the construct to press together the two pieces joined at their complementary surfaces; and applying an electrical current to the powder in the construct to initiate an oxidation-reduction reaction, thereby bonding the carbon-carbon composite pieces together.