Shadia Jamil Ikhmayies¹; ¹Al Isra University

Thermo-Calc software was used to determine the temperature-composition phase diagram of Si-B binary system at a pressure of 1 bar. There are six phases; liquid, diamond-Si, β-B, SiB3, SiB6, and SiBn. In addition to the six single phase regions, the phase diagram shows nine mixed two-phase regions, which are all thoroughly discussed. There are two peritectic reactions; the first one is: Liquid + β-B ↔ SiBn at 2310.04 K and 8.165 Si mass percent, and the second is Liquid+ SiBn ↔ SiB6 at 2122.98 K, and 29.447 Si mass percent. The phase diagram also shows a eutectic reaction, which is: Liquid ↔ Diamond Si+SiB6 at 1657.56 K and 96.715 Si mass percent. In addition, it shows a peritectoid reaction, which is: Diamond Si + SiB6↔SiB3 at 1443.01 K and 99.715 Si mass percent. The melting point of β-B is 2347.85 K and that of diamond Si is 1687.00 K.