一、前言大功率汽轮机末级动叶片,经常处在饱和蒸汽范围内工作,强烈的受到蒸汽中水滴的冲蚀作用,由于单机容量的迅速增大,长度超过1米的低压末级动叶顶部线速度已超过音速高达600米/秒左右的情况下,大大超过现有机组的最大值,使动叶片更容易受到水蚀损伤。由于严重的水蚀作用,机组运行的可靠性受到很大的影响,对水蚀严重叶片的修补或更换叶片又必须停机很久将给国民经济造成很大损失。因此末级动叶片的水蚀也 I. INTRODUCTION The last stage of high-power turbine rotor blades, often in the saturated steam range, strongly affected by water droplets in the steam erosion, due to the rapid increase of stand-alone capacity, the length of more than 1 m at the top of the low-pressure rotor blade Line speed has exceeded the speed up to about 600 m / s, greatly exceeding the maximum of existing units, making the rotor blades more susceptible to water damage. Due to serious water erosion, the reliability of the operation of the unit is greatly affected. For the repair and replacement of blades with severe water erosion, they must be shut down for a long time, which will cause great losses to the national economy. So the last stage moving blades of water also