Ni3Al-B ALLOYS AND THEIR MECHANICAL PROPERTIES AT HIGH TEMPERATURES

The Ni-22Al-0.5B and Ni-24Al-0.5B alloys (at.%) were prepared by a vacuum induction melting process followed by a gravity casting process. The castings were directionally solidified in a resistance furnace at a temperature of 1550 degrees C and rate of directional solidification of 50 mm.h(-1). The castings and ingots after directional solidification were used for preparation of samples for a compression test. These tests were carried out at a temperature of 800 degrees C and deformation rate of 5.10(-2) s(-1). The samples were shaped as a short cylinder (8 x 12 mm). The results of the compression tests have confirmed that the directionally solidified Ni3Al alloys alloyed with boron have a higher yield strength than the castings of these alloys and the Ni3Al alloys unalloyed with boron.