(1. 桂林電子科技大學 材料科學與工程學院,桂林 541004;
2. 哈爾濱工業(yè)大學 材料科學與工程學院,哈爾濱 150001;
3. 三峽大學 機械與動力學院,宜昌 443002)
摘 要: 系統(tǒng)研究Nb-Ti-Co三元合金系富Nb角相區(qū)滲氫成分區(qū)域內(nèi)27種合金(膜)在523~673 K下的滲氫性能,并與Nb-Ti-Ni合金和純Pd進行比較;而后分析區(qū)域內(nèi)代表性合金(18#, 17#, 25#, 24#和33#)的持久性能、氫溶解和氫擴散特性,并結合“電阻模型”詳細探討Nb-Ti-Co合金(膜)的滲氫和抗氫脆機理。結果表明:在原有滲氫成分區(qū)域內(nèi)排除六種氫脆合金后,重構滲氫區(qū)域,即區(qū)域III'''',該區(qū)域內(nèi)18#合金(Nb65Ti20Co15)在673 K下具有最大的滲氫系數(shù),為4.12×10-8 mol/(m·s·Pa1/2),其余合金按照滲氫系數(shù)高低(取前三)的排列順序依次為17#、25#和24#,三者滲氫系數(shù)分別為3.99×10-8、3.72×10-8和3.58×10-8 mol/(m·s·Pa1/2);區(qū)域內(nèi)33#、24#和18#合金的氫溶解和氫擴散系數(shù)依次增加,18#合金的氫溶解和氫擴散系數(shù)為15.6 mol/(m3·Pa0.5)和26.4×10-10 m2/s,分別是33#合金的1.16和1.35倍;區(qū)域III′內(nèi)合金滲氫系數(shù)的增加(Ф18#>Ф24#>Ф33#)歸結于同時增大的氫溶解和擴散系數(shù),但后者起主要作用,18#合金的氫擴散激活能較低,氫原子容易躍遷,因此,該合金具有相對較高的氫擴散系數(shù)。
關鍵字: Nb-Ti-Co合金;氫滲透;氫溶解;氫擴散
(1. School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China;
2. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
3. College of Mechanical and Power Engineering, Three Gorges University, Yichang 443002, China)
Abstract:The hydrogen permeability of 27 kinds of alloys in the hydrogen permeable component region of Nb-Ti-Co alloy system was studied in the region of 523-673 K, and compared with Nb-Ti-Ni and pure Pd. And then the durable performance, hydrogen dissolution and diffusion behaviors of typical alloys in the above component region were analyzed. The hydrogen permeable and anti-hydrogen brittleness mechanisms were also discussed by using the resistance model and the hydrogen dissolved model. The results show that after removing 6 hydrogen embrittlement alloys in original hydrogen permeable component region, an new component region was constructed, i.e., the region III''''. 18# alloy in the region III′ possesses the highest hydrogen permeability with 4.12×10-8 mol/(m·s·Pa1/2) at 673 K. The hydrogen permeability of the remaining alloys is listed in the order as follows: 17# (3.99×10-8 mol/(m·s·Pa1/2)), 25# (3.72×10-8 mol/(m·s·Pa1/2)) and 24# (3.58×10-8 mol/(m·s·Pa1/2)). The hydrogen dissolution and diffusion coefficients of 33#, 24# and 18# alloys in the region III'''' increase in sequence. The hydrogen dissolution and diffusion coefficients of 18# alloy are 15.6 mol/(m3·Pa0.5) and 26.4×10-10 m2/s, which are 1.16 and 1.35 times larger than those of 33# alloy. The increase of hydrogen permeability in the region III''''(Ф18#>Ф24#>Ф33#) can be attributed to the simultaneous increment of hydrogen dissolution and diffusion coefficient, but the later plays a key role. The hydrogen diffusion activation energy of 18# alloy is low and the hydrogen atoms are easy to jump. Therefore, this alloy has relatively high hydrogen diffusion coefficient.
Key words: Nb-Ti-Co alloy; hydrogen permeation; hydrogen dissolution; hydrogen diffusion


