Abstract: Haynes 230 is an important candidate material for high temperature components in ultra-high temperature gas-cooled reactors， concentrating solar power and advanced ultra-supercritical coal-fired generating plants.In order to establish the alloy microstructure control criterion， it adopts the hot-rolled forming plate and adjusts the solid solution temperature，the law of microstructure evolution of the behavior of precipitation phase dissolution and the change of grain size during solution treatment were studied，The results showed that the hot-rolled plates were composed of equiaxed austenitic grains with the average grain size of 32 μm. the main precipitation phase was detected to be M6C carbide and the metal cluster M was composed of W and Mo. The carbide content and particle size of M6C varied little and the austenitic grains coarsened little during solution treatments in the temperature range of 950-1 150 ℃. With the increasing of solid solution temperature to 1 180-1 200 ℃， the carbide content of M6C decreased， the particle size decreased， and the grain was coarening；At 1 230 ℃ and 1 250 ℃， the dissolution of M6C and the coarsening of grains became obviously with the average grain size to be 142 μm and 201 μm， respectively. Tensile strength at room temperature and 750 ℃ decreased slightly with the increasing solution temperature ， while tensile strength at 900 ℃ increased. The grain size and the related solution temperature was recommended to be controlled in rang of 76-142 μm and 1 200-1 230 ℃ based on the present experimental investigation， respectively.

Key words: Haynes 230 Alloy, Solution Treatment, Grain Size, Carbide

摘要： Haynes 230合金是超高温气冷堆、光热发电和先进超超临界燃煤发电机组高温部件的重要候选材料。为了建立合金显微组织控制准则，采用热轧成形板材，通过调整固溶温度，研究了固溶处理过程中析出相溶解行为和晶粒尺寸变化等显微组织演变规律，研究结果显示，热轧态板材具有奥氏体等轴晶组织，晶粒分布均匀，平均晶粒尺寸约为32 μm，主要析出相为富W和Mo的M6C碳化物；在950~1 150 ℃，M6C碳化物含量和颗粒尺寸未发生明显变化，晶粒尺寸变化缓慢；随着固溶温度增高到1 180~1 200 ℃，M6C碳化物含量有所降低，颗粒尺寸减小，晶粒发生粗化；当固溶温度升高到1 230、1 250 ℃时，碳化物含量和尺寸明显减小，平均晶粒尺寸增至142、201 μm；随着固溶温度增高，室温和750 ℃拉伸强度趋于降低，900 ℃抗拉强度升高；基于试验研究，提出Haynes230合金热轧板材晶粒尺寸控制在76~142 μm，相应的固溶温度选用1 200~1 230 ℃。

关键词: Haynes 230合金, 固溶处理, 晶粒尺寸, 碳化物