Titanium nitride is also produced intentionally within some steels by judicious addition of titanium to the alloy. TiN forms at very high temperatures because of its very low enthalpy of formation, and even nucleates directly from the melt in secondary steelmaking. It forms discrete, micrometre-sized cubic particles at grain boundaries and triple points, and prevents grain growth by Ostwald ripening up to very high homologous temperatures. Titanium nitride has the lowest solubility product of any metal nitride or carbide in austenite, a useful attribute in microalloyed steel formulas.