APPLICATIONS OF DIBM TO SURFACE MODIFICATION OF CAVITATION DAMAGE FOR TURBINE MATERIALS

摘要

Cavitation damage of turbines has been one of general but very difficult problems inrnwater power stations. Because of cavitation damage, repair cycles of many largescalernwater turbines are forced to change to three or two years from four years, andrnrepair costs big and repair times long. It affects productions of electricity and bringsrnabout heavy economic losses. DIBM (dynamic ion beam mixture), developed inrnrecent years, has been firstly used in turbine material 0Cr13Ni9Ti to modify surfacernperformance of cavitation resistance, and better effects have been obtained in thisrnpaper. Meanwhile, where material 0Cr13Ni9Ti is concerned, DIBM has much betterrneffects than routine ion implantation. The effect of surface modification of cavitationrndamage reaches more than 3 times of that before treatment in measure of WLRrn(weight loss rate). In addition, a new index CDT (cavitation damage time) is firstlyrnpresented, being much more suitable than WLR for measure of cavitation damage.