单晶高压涡轮外环块再结晶缺陷控制

Recrystallization Defect Control of Outer Ring Block of Single Crystal High Pressure Turbine

分析了新型发动机燃烧室高压涡轮外环块铸件的结构、铸造工艺因素对单晶铸件再结晶缺陷的影响,设计了DD5和DD6两种二代单晶高温合金定向凝固单晶铸造的试验方法,研究了典型单晶铸件DD6单晶合金高压涡轮外环块的再结晶缺陷类型和形成机理。通过采取优化工序流程、优化产品结构、增加工艺补贴等措施,将该高压涡轮外环块的再结晶缺陷从95%降低到10%以下,极大提升了单晶铸件的单晶完整性及产品合格率,降低了研制成本,提高了该铸件高温力学性能及使用可靠性。

The influence of the structure and casting process factors on recrystallization defects of the outer ring block of the high-pressure turbine in the combustion chamber of a new type of engine was analyzed.The test methods of directional solidification single crystal casting of DD5 and DD6 second generation single crystal superalloy were designed.The types and formation mechanism of recrystallization defects of the outer ring block of the high-pressure turbine of DD6 single crystal castings were studied.By adopting measures such as optimizing process flow,optimizing product structure,and increasing process subsidies,the recrystallization defect of the outer ring block of the high-pressure turbine was reduced from 95%to less than 10%,which greatly improved the single crystal integrity and product qualification rate of the single crystal casting,reduced the development cost,and improved the high temperature mechanical properties and service reliability of the casting.