Cu含量对新型AlNiZrCoYSi高熵非晶合金非晶形成能力与耐腐蚀性能的影响

Effect of Copper Content on Corrosion Resistance and Glass-formingAbility of Novel AlNiZrCoYSi High Entropy Amorphous Alloy

摘要:

采用高真空电弧熔炼喷射成形技术制备了一种新型Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅高熵非晶合金条带,并研究了Cu元素的添加及含量变化对Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅高熵非晶合金耐腐蚀性能的影响。利用X射线衍射仪(XRD)、差示扫描量热仪(DSC)、显微硬度计分别研究了合金材料的非晶形成能力与硬度；通过极化曲线(Tafel)和Nyquist图等电化学方法考察了高熵非晶合金室温下在3.5 wt.% NaCl水溶液中的耐腐蚀性能。结果表明：四种(AlNiZrCo)_75-xCu_xY₂₀Si₅(x=0, 10, 14, 15)近等原子比高熵非晶合金均呈现典型的非晶态衍射峰,Cu含量对AlNiZrCoYSi高熵非晶合金的非晶形成能力影响不大,但会降低合金的抗腐蚀性能,且上述合金的维氏显微硬度均超过470 HV_0.1。其中,Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅高熵非晶合金的耐腐蚀性能最佳,其自腐蚀电位(E_corr)为-0.248 V,自腐蚀电流密度(i_corr)为1.63 μA/cm^₂,极化电阻(R_p)为24.56 kΩ.cm^₂,该材料在解决严苛海洋环境下防腐耐磨问题具有较大的应用潜力。

Abstract:

A new type of high entropy amorphous alloy (denoted as HEAA) ribbons Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅ was prepared by injection in copper mould with arc melting. The effect of Cu content on corrosion resistance of the Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅ HEAA was studied mainly by adding Cu element into the alloy. The glass-forming ability and hardness of the alloy were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and microhardness tester, respectively. The corrosion resistance of these ribbons in 3.5 wt.% NaCl corrosive solution at room temperature were investigated by potentiodynamic polarization curves (Tafel) and Nyquist plots. The results show that four kinds of (AlNiZrCo)_75-xCu_xY₂₀Si₅(x=0, 10, 14, 15) near equiatomic HEAA ribbons present typical amorphous diffraction peaks. The Cu content has little effect on the glass-forming ability of the AlNiZrCoYSi HEAA ribbons, but it will reduce the corrosion resistance. The Vickers microhardness of the above alloys is over 470 HV_0.1. The corrosion resistance of the Al_17.5Ni₂₀Zr_17.5Co₂₀Y₂₀Si₅ HEAA ribbons is the finest. The corrosion potential (E_corr) is -0.248 V, the corrosion-current density (i_corr) is 1.63 μA / cm^₂, and the polarization resistance (R_P) is 24.56 kΩ.cm^₂. This material has demanding application potential to solve the problem of anti-corrosion and wear resistance in harsh marine environment.