Cr元素对Fe基块体非晶合金形成能及腐蚀性能影响的研究

利用微合金化技术,制备了Fe_68.4-xCo_7.6Si₇B₁₀P₅C₂Cr_x (x=0, 1, 2, 3)非晶合金,并分别使用单辊急冷甩带法和铜模铸造法制备了带状和棒状样品。借助XRD、DSC、DTA表征该非晶合金系的热力学性能与非晶形成能；并进一步采用电化学动电位极化曲线法研究了该非晶合金系在硫酸溶液中的的耐腐蚀性能。实验结果表明,通过微量添加Cr元素的方法,使该合金系的非晶形成能普遍提高,当Cr元素添加量为2%时,获得了该系列非晶合金中的最大过冷液体区间(ΔTx=57K),并且成功制备了直径为5mm的圆棒状样品；同时,由于Cr元素的添加,在1N浓度的硫酸溶液中,材料表面上形成富含Cr元素的保护层,可以有效阻止材料内部的进一步腐蚀,耐腐蚀性能明显得到改善。

Effect of Cr Element on the Forming Ability and Corrosion Properties of Fe-based Bulk Amorphous Alloys

Using micro alloy technology, Fe_68.4-xCo_7.6Si₇B₁₀P₅C₂Cr_x (x=0, 1, 2, 3) bulk amorphous alloys were prepared. The ribbon and rod samples were prepared by single-roller melt spinning and copper mold casting, respectively. The thermodynamic properties and forming ability of the bulk amorphous alloys were characterized by using XRD, DSC and DTA. Further, the corrosion behaviors of the amorphous alloys were tested in H₂SO₄ solution by using potentiodynamic polarization method. The experimental results showed that the forming ability of the amorphous alloys increased with the addition of Cr element. Moreover, in the 1N H₂SO₄ solution, a protective layer rich in Cr elements formed on the surfacr of the alloy because of the addition of Cr element, which can effectively prevent the further corrosion of the material. Therefore, the corrosion resistance was improved significantly