Preparation of Corrosion-Resistant Bulk Amorphous Alloys

耐腐蚀大块非晶合金的制备

基本信息

批准号：
11650731
负责人：
HABAZAKI Hiroki
金额：
$ 2.37万
依托单位：
HOKKAIDO UNIVERSITY (2000)Tohoku University (1999)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650731/
关键词：
Amorphous alloys Bulk materials Corrosion resistance Copper mold casting Gas atomization Sheath rolling Super-cooled liquid Spontaneous passivation バルク合金ナノ結晶不働態 TEM

项目摘要

Corrosion-resistant bulk Ni-Cr-Nb-P-B, Ni-Cr-Ta-P-B and Ni-Cr-Me-P-B alloys with cylindrical shape of 1 and 2 mm diameter are prepared by a copper mold casting method. A good correlation between the glass forming ability and stability of super-cooled liquid state has been found for these alloy systems except the molybdenum-containing alloy system. The bulk amorphous alloys thus prepared are spontaneously passive even in very aggressive 6M and 12M HCl solutions open to air at 303 K.The bulk amorphous alloys reveal the same anodic and cathodic polarization curves as the corresponding melt-spun alloy ribbons, as far as amorphous single phase alloys are obtained. Precipitation of fcc Ni phase in the bulk amorphous alloys is detrimental to the corrosion resistance of the alloys. The influence of the precipitation is, however, strongly dependent upon the size of the precipitates. When fcc Ni with size of 20〜nm is formed in the amorphous matrix, the alloys show about two orders of magnitude higher passive current density in comparison with the amorphous single phase alloys. In contrast, precipitation of fcc Ni with only 2-3 nm size results in the increase only twice in the passive current density. Bulk amorphous Ni-10Cr-5Nb-16P-4B alloy plates of 2 mm thickness are also prepared by consolidation of gas-atomized amorphous alloy powders by sheath rolling at a super-cooled liquid state, that is, 708 K.The bulk alloy thus prepared is found to reveal similar extremely low corrosion rate in 6M HCl at 303 K to the corresponding melt-spun alloy. However, in 12M HCl solution, the sheath-rolled alloy shows preferential corrosion attack at boundaries of the gas-atomized powders, possibly due to the influence of the oxidation of the particle surface during heating for consolidation. Thus, further improvement of the preparation processes to obtain highly corrosion-resistant bulk amorphous alloys using this method.

通过铜模具铸造方法制备了耐腐蚀的大量NI-CR-NB-P-B，NI-CR-TA-P-B和Ni-CR-ME-P-B合金，其直径为1和2 mm的圆柱形形状为1和2 mm。除含钼合金系统以外的这些合金系统的玻璃形成能力与超冷液态的稳定性之间存在良好的相关性。这样制备的大量非晶合金即使在303 K时向空气开放的非常侵略性的6m和12m HCl溶液中也是被动的。散装的无定形合金揭示了与相应的阳极偏振曲线与相应的熔融合金型曲线相同，直到相应的熔融合金元素，就具有不良的单相合金而言。大块无定形合金中FCC Ni相的沉淀对合金的耐腐蚀性有害。但是，降水的影响很大程度上取决于沉淀物的大小。当在无定形基质中形成具有20至nm的FCC Ni时，与无定形单相合金相比，合金显示出大约两个较高的被动电流密度的阶。相比之下，只有2-3 nm大小的FCC Ni的降水导致被动电流密度仅增加两次。 Bulk amorphous Ni-10Cr-5Nb-16P-4B alloy plates of 2 mm thickness are also prepared by consolidation of gas-atomized amorphous alloy powders by Sheath rolling at a super-cooled liquid state, that is, 708 K.The bulk alloy thus prepared is found to reveal similar extremely low corrosion rate in 6M HCl at 303 K to the corresponding melt-spun alloy.然而，在12M HCl溶液中，鞘合金在气体粉末的边界处显示出优先的腐蚀攻击，这是由于在加热过程中粒子表面的氧化影响而可能导致的。这进一步改善了使用此方法获得高度耐腐蚀的体积非晶合金的制备过程。