K418高温合金叶轮脉冲激光再制造形状与性能控制

Forming and performance control of pulsed laser remanufacturing for K418 alloy impeller

摘要:

针对K418高温合金叶轮材料成本高、制造工艺复杂以及体积损伤频繁的实际，以该牌号体积损伤叶轮再制造为目标，设计了成分接近、工艺匹配的成形粉材，基于波形可调制 脉冲激光优化工艺，实现了形状和性能的再生。试验结果表明：叶片成形后表层及内部无裂纹，成形部位与基体为冶金结合，加工后尺寸精度在1mm以内，形变精度在0.03mm以内，成形层显微硬度为900~1400 HV0.1，超过基体20%。在高温动转平衡试验下，叶轮最大转数达13500 r/min，最大振幅0.4mm，无明显偏转及喘振现象，符合动平衡性能要求。

Abstract:

Aiming at the high material cost of K418 cast super alloy impeller, the complex manufacturing process and the currently volume damage, the laser remanufacture for edge volume damage of this type was taken for target, the composition approached and process matched alloy was designed, the shape and performance was recovered by using the waveform modulated pulse laser. The results of experiments show that, there were no surface and internal cracks existed，there was metallurgical bonding between the forming layer and the substrate, the forming precision was within 1mm, the deformation precision is within 0.03mm, the surface hardness of the forming zone was 900~1400 HV0.1 , which is 20% higher than the substrate. Under the high temperature dynamic balance test, the maximum rotation of the impeller is 13500 r/min, the maximum amplitude is 0.4mm, there is no exception, no deflection and surge existed, which meet the dynamic balance performance requirements.