电镀稀土铬提高水轮机的抗空蚀磨损能力

PLATING RARE EARTH CHROMIUM ON HYDRAULIC TURBINE'S SUBSTRATES TO IMPROVE RESISTANCE TO CAVITATION EROSION AND ABRASION

在不锈钢水轮机母材上 ,用周期反相电镀稀土铬 ,镀层厚度约 0 3mm ,镀层由金属基相和稀土盐颗粒第二相组成 ,硬度为 90 0Hv～ 10 0 0Hv .阳极极化曲线测量表明 :镀层的腐蚀阻力为母材的 7～ 8倍 .在模拟式小水轮机上考核 ,镀层的抗磨蚀性为母材的 2 5～ 2 8倍 ,为离子氮化不锈钢的 10～ 12倍 .在水电生产中应用 ,电镀水轮机的工作寿命比原不锈钢高 2～

Plating rare earth chromium on stainless steel applied in hydraulic turbine,by means of the operation converting electrodes periodically,was carried out.The plating layer consists of metallic matrix and second phase particles of rare earth sulphates or carbonates,its thickness is about 0.3mm,its microhardness is from Hv900 to 1000.The results of anodic polarization curves indicate that the corrosive resistance of plating layer is 7～8 times to that of stainless steel substrates.When an imitating small hydraulic turbine made up of different materials was rotated in the slurry of 60% water and 40% sands,the resistance of plating layer to cavitation erosion and abrasion is about 28 times to that of stainless steel,and is 10～12 times to that of plasma-nitrided stainless steel.The results of hydraulic electricity generation indicate the service life of plated hydraulic turbine is 3～6 times to that of stainless steel hydraulic turbine.