Evolution of TiN inclusion in solid state Fe-based alloy during heating at 1473 and 1673 K was studied by using Fe-36Ni alloy to avoid any unexpected influence of austenite-ferrite phase transformation of alloy on the observation of TiN inclusions in post-annealed samples. Average size of fine TiN inclusions smaller than 2 µm firstly decreased but changed to the increasing tendency during heating at 1473 K, reflecting the initial dissolution of TiN inclusion in Fe-Ni matrix followed by gradual growth of inclusion by Ostwald ripening. On the contrary, heating at 1673 K resulted in the monotonous decrease in average size of TiN inclusion in the size range up to 5 µm. It was considered that above mentioned different TiN inclusion evolution during heating at 1473 or 1673 K was due to the different solubility of TiN depending on temperature; thermodynamic calculation revealed that approximately 40% of TiN inclusion existing at room temperature may dissolve at 1673 K whereas only few may dissolve at 1473 K.

使用 Fe-36Ni 合金研究了在 1473 和 1673 K 加热过程中固态铁基合金中 TiN 夹杂物的演变，以避免合金的奥氏体-铁素体相变对后退火样品中 TiN 夹杂物的观察产生任何意外影响. 小于 2 µm的细小 TiN 夹杂物的平​​均尺寸在 1473 K 加热过程中先减小后呈增大趋势，反映了 TiN 夹杂物在 Fe-Ni 基体中的初始溶解，随后通过 Ostwald 熟化过程中夹杂物逐渐长大。相反，在 1673 K 加热导致尺寸范围高达 5 µ的 TiN 夹杂物的平​​均尺寸单调减小米。认为上述不同的 TiN 夹杂物在 1473 或 1673 K 加热过程中的演变是由于 TiN 的溶解度随温度不同；热力学计算表明，室温下大约 40% 的 TiN 夹杂物可以在 1673 K 下溶解，而只有少数可以在 1473 K 下溶解。