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K273高温合金的铸态组织是在奥氏体基体的树枝晶间,半连续地分布着共晶状(Gr、M_0、W)_7C_3和笔迹状 N_bC 碳化物。提高凝固速度可以减少树枝晶间臂距和共晶碳化物层片间距,从而减小萌生于共晶碳化物处的显微裂纹尺寸,提高材料的高温性能。K273高温合金在600～700℃下工作,其组织和性能具有良好的长期稳定性。在650～816℃中温热处理发生 M_7C_3转变为 M_(23)C_6的相反应。相反应的结果提高合金的屈服强度和铸件的综合高温性能。
The as-cast microstructure of K273 superalloy is composed of semi-continuous distribution of eutectic (Gr, M_0, W) _7C_3 and hand-like N_bC carbides between dendrites of austenite matrix. Increasing the solidification rate can reduce the inter-dendritic arm spacing and eutectic carbide layer spacing, thereby reducing the size of the microcrack at the eutectic carbide and increasing the high temperature properties of the material. K273 superalloy at 600 ~ 700 ℃ work, the organization and performance has good long-term stability. The phase transition of M_7C_3 to M_ (23) C_6 occurred in the temperature range of 650 ~ 816 ℃. The result of the phase reaction increases the yield strength of the alloy and the overall high-temperature properties of the casting.