电子束熔炼Ti-6Al-4V在高压氢气中的疲劳裂纹扩展

Fatigue Crack Growth of Electron Beam Melted Ti-6Al-4V in High-Pressure Hydrogen.

作者信息

Neikter M, Colliander M, de Andrade Schwerz C, Hansson T, Åkerfeldt P, Pederson R, Antti M-L

机构信息

Division of Materials Science, Luleå University of Technology, 97181 Luleå, Sweden.

Division of Subtractive and Additive Manufacturing, University West, 46132 Trollhättan, Sweden.

出版信息

Materials (Basel). 2020 Mar 12;13(6):1287. doi: 10.3390/ma13061287.

DOI:10.3390/ma13061287

PMID:32178389

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7143723/

Abstract

Titanium-based alloys are susceptible to hydrogen embrittlement (HE), a phenomenon that deteriorates fatigue properties. Ti-6Al-4V is the most widely used titanium alloy and the effect of hydrogen embrittlement on fatigue crack growth (FCG) was investigated by carrying out crack propagation tests in air and high-pressure H environment. The FCG test in hydrogen environment resulted in a drastic increase in crack growth rate at a certain Δ K, with crack propagation rates up to 13 times higher than those observed in air. Possible reasons for such behavior were discussed in this paper. The relationship between FCG results in high-pressure H environment and microstructure was investigated by comparison with already published results of cast and forged Ti-6Al-4V. Coarser microstructure was found to be more sensitive to HE. Moreover, the electron beam melting (EBM) materials experienced a crack growth acceleration in-between that of cast and wrought Ti-6Al-4V.

摘要

钛基合金易受氢脆（HE）影响，这是一种会使疲劳性能恶化的现象。Ti-6Al-4V是使用最广泛的钛合金，通过在空气和高压氢环境中进行裂纹扩展试验，研究了氢脆对疲劳裂纹扩展（FCG）的影响。在氢环境中的FCG试验导致在一定ΔK下裂纹扩展速率急剧增加，裂纹扩展速率比在空气中观察到的高出13倍。本文讨论了这种行为的可能原因。通过与已发表的铸造和锻造Ti-6Al-4V的结果进行比较，研究了高压氢环境下FCG结果与微观结构之间的关系。发现较粗大的微观结构对氢脆更敏感。此外，电子束熔炼（EBM）材料的裂纹扩展加速情况介于铸造和锻造Ti-6Al-4V之间。