耐磨性的影響
(華南理工大學(xué) 機(jī)械工程學(xué)院，廣州 510641)
摘 要: 研究鋁合金化學(xué)鍍Ni-W-P三元合金的耐磨性能，探討鎢含量對鋁合金(LY12)化學(xué)鍍Ni-W-P耐磨性和硬度的影響。結(jié)果表明：鋁合金表面化學(xué)鍍Ni-W-P三元合金在400 ℃加熱1 h后，表面硬度達(dá)HV251 080，表面硬度和耐磨性均較基體提高10倍以上；但過高的W含量，使得表面硬度下降。磨損實(shí)驗(yàn)發(fā)現(xiàn)，試樣產(chǎn)生了鍍層碎裂和剝落現(xiàn)象。其主要原因是由于鋁合金基體與鍍層熱膨脹系數(shù)的差異及Ni3P的析出導(dǎo)致應(yīng)力過大，引起鍍層硬度和耐磨性隨著W含量的增加而下降。并用化學(xué)鍍Ni-W-P合金沉積機(jī)理解釋了鍍層成分分布特征的形成原因。
關(guān)鍵字: Ni-W-P合金；化學(xué)鍍；耐磨性
of electroless Ni-W-P plating on aluminium alloy
（College of Mechanical Engineering, South China University of Technology, Guangzhou 510641, China）
Abstract:The wear resistance of electroless Ni-W-P coatings on aluminium alloy was studied, the effect of content of tungsten on the wear resistance and hardness of electroless Ni-W-P deposits was discussed. The results show that the hardness of deposit heated at 400 ℃ for 1 h is HV251 080, and the wear resistance and hardness of deposits heated at 400 ℃ for 1 h are ten times more than those of aluminium matrix. With increasing content of W, the hardness of Ni-W-P coatings decreases. Disintegration and spall on the Ni-W-P deposits heated at 400 ℃ for 1 h were generated after abrasion test because of the excessive stress caused by different coefficient of thermal expansion between matrix materials and deposits and precipitation of Ni3P. The characteristic of electroless Ni-W-P deposits composition distribution is explained by aggradational deposition mechanism of electroless Ni-W-P deposits.
Key words: Ni-W-P alloy; electroless plating; wear resistance
