(華南理工大學(xué) 機(jī)械與汽車工程學(xué)院，廣州 510640)
摘 要: 采用中性鹽霧加速試驗(yàn)、掃描電鏡、X射線衍射儀、光電子能譜儀等研究了Cu-17Ni-3Al-X合金在中性鹽霧中的腐蝕行為。結(jié)果表明：在中性鹽霧腐蝕過程中，該合金具有良好的耐鹽霧腐蝕性能，合金的腐蝕速率隨腐蝕時(shí)間的延長而迅速降低，腐蝕480 h后平均腐蝕速率僅為0.010 mm/a。這是因?yàn)楦g后合金表面生成一層致密的Cu2O膜，隨著腐蝕的進(jìn)行，Cu2O膜增厚，同時(shí)外層的Cu2O膜被進(jìn)一步氧化生成疏松的Cu2(OH)3Cl顆粒。合金在中性鹽霧中腐蝕后，主要是a(Cu)固溶體被腐蝕，合金中的第二相仍殘留在晶界處。
關(guān)鍵字: Cu-Ni合金；中性鹽霧試驗(yàn)；腐蝕速率；腐蝕產(chǎn)物膜；選擇性腐蝕
（School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China）
Abstract:The corrosion behavior of the Cu-17Ni-3Al-X alloy was investigated by means of neutral salt spray test, scanning electronic microscope, X-ray diffraction and X-ray photoelectron spectroscope. The results show that the alloy possesses great resistance to the salt atmosphere. The corrosion rate of the alloy decreases rapidly with the increase of exposure time. After being corroded for 480 h, the average corrosion rate is only 0.010 mm/a. Due to the uniform Cu2O film formed on the surface of the specimen, the underlying substrate is well protected and the corrosion rate of the alloy is highly reduced. With the increase of the exposure time, the Cu2O film is thickened and the outer layer of the Cu2O film is oxidized to granular Cu2(OH)3Cl film. The corrosion in neutral salt atmosphere occurs mainly in a(Cu) matrix of the samples. However, the second phases remain at the grain boundary.
Key words: Cu-Ni alloy; neutral salt spray test; corrosion rate; corrosion product film; selective corrosion
