Abstract
The partial phase diagram in the Th-C system between pure Th and ThC was studied by metallographic and X-ray techniques and by measurements of electrical resistivity in quenched and slow cooled Th-C alloys. The peritectic point of the reaction, liq.+ThC \
ightleftarrows α-Th, was found at 16 at%C and about 1875°C and the peritectic composition of ThC was 33 at%C. The eutectic reaction occurred at 1650°C and its composition of α-Th and β-Th was 6.5 and <0.5 at%C, respectively. The α\
ightleftarrowsβ transformation temperature rose gradually with the carbon content up to 2.3 at%C and rose rapidly between the compositions of 2.3 and 3.7 at%C. The phase boundaries of α/ThC+α, ThC+α/ThC, ThC/ThC+ThC2 and liq.+ThC/ThC were also established.
