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采用单辊急冷法制备了57.5Ni-24.5Fe-14.5W-3.5B(质量分数,%)非晶薄带,并在不同温度下进行退火。用DSC和XRD分析了非晶薄带的晶化行为及析出相的演变过程;用电化学极化曲线及电化学阻抗法研究了试样在3.5%NaCl溶液中的电化学腐蚀行为;用SEM和EDS分析了试样腐蚀后的表面显微形貌及成分。结果表明:该非晶薄带的晶化过程分为3步,其晶化温度约为430,470和700℃;退火试样的耐腐蚀性整体优于非晶合金样,部分晶化试样的抗电化学腐蚀性能优于完全晶化试样;500℃退火试样表面形成致密钝化膜,抗腐蚀性能优异,而非晶薄带和720℃退火试样形成的钝化膜不稳定,易被点蚀和局部腐蚀。
Single-roll rapid cooling method was used to prepare 57.5Ni-24.5Fe-14.5W-3.5B (mass fraction,%) amorphous ribbons and annealed at different temperatures. The crystallization behavior and the evolution of the precipitated phase were analyzed by DSC and XRD. The electrochemical corrosion behavior of the sample in 3.5% NaCl solution was studied by electrochemical polarization curve and electrochemical impedance spectroscopy. SEM, And EDS analyzed the surface micro-morphology and composition of the sample after corrosion. The results show that the crystallization process of the amorphous ribbon is divided into three steps, the crystallization temperature is about 430,470 and 700 ℃. The corrosion resistance of the annealed sample is better than that of the amorphous alloy. The resistance of the partially crystallized sample The electrochemical corrosion performance is better than the completely crystallized sample; the dense passive film formed on the surface of the annealed sample at 500 ℃ has excellent corrosion resistance, while the passive film formed by amorphous ribbon and annealed at 720 ℃ is not stable Pitting and local corrosion.