Effects of High Pressure Hydrogen on Mechanical Properties of 6061 Aluminum Alloy
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摘要: 6061铝合金是铝内胆、碳纤维、全缠绕气瓶的重要原材料,其氢气相容性直接影响气瓶的安全可靠性,但目前缺少国产6061铝合金的氢气相容性数据。为研究高压氢气对国产6061铝合金力学性能的影响,选取2种热处理工艺的国产6061铝合金在高压氢气环境下进行慢应变速率拉伸试验和疲劳裂纹扩展试验。试验结果表明,国产6061铝合金具有良好的氢气相容性,氢气对慢应变速率拉伸性能和疲劳裂纹扩展性能的影响均较小。同时,热处理工艺对6061铝合金氢脆敏感性无明显影响。Abstract: The 6061 aluminum alloy is an important raw material for aluminum liner carbon fiber full-wrapped composite gas cylinders, whose hydrogen compatibility determines to a great degree the safety and reliability of gas cylinders.However, the data is lacking in China concerning its hydrogen compatibility.In order to investigate the effects of high pressure hydrogen on the mechanical properties of the domestically fabricated 6061 aluminum alloy, the slow strain rate tests and fatigue crack growth rate tests for it were carried out under two heat treatment conditions.The test results show that the 6061 aluminum alloy has good compatibility with hydrogen, and hydrogen has little effect on its slow strain rate tensile properties and fatigue crack growth properties.Meanwhile, it was also found that heat treatment has little influence on its hydrogen embrittlement sensitivity.
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Key words:
- 6061 aluminum alloy /
- mechanical property /
- high pressure hydrogen /
- heat treatment
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表 1 6061铝合金棒材化学成分
Table 1. Chemical composition of 6061 aluminium alloy bar
(%) Si Fe Cu Mn Mg Cr Zn Ti Pb Bi Others Al 0.69 0.22 0.29 0.070 1.05 0.23 0.013 0.030 0.001 <0.000 3 <0.15 97.4 表 2 6061铝合金板材化学成分
Table 2. Chemical composition of 6061 aluminum alloy sheet
(%) Si Fe Cu Mn Mg Cr Ti Al 0.65 0.36 0.30 0.005 1.11 0.15 0.040 97.4 表 3 6061铝合金热处理工艺
Table 3. Heat treatment of 6061 aluminum alloy
Team Solution
temperature/(℃)Solution
time/(h)Aging
temperature/(℃)Aging
time/(h)A 546 2 180 8 B 546 2 240 1 表 4 6061铝合金力学性能
Table 4. Mechanical properties of 6061 aluminum alloy
Team Tensile strength/
(MPa)Yield stress/
(MPa)Elongation after
fracture/(%)Reduction of
area/(%)A-H2 350.5 302.1 16.44 41.41 A-Ar 355.3 309.5 17.09 41.91 B-H2 352.1 316.7 13.89 38.89 B-Ar 352.9 320.7 15.41 40.00 表 5 Paris模型拟合结果
Table 5. Fitted results of Paris model
Team C/(10-10) m R2 A-H2 4.76 2.36 0.994 A-Ar 5.75 2.39 0.997 B-H2 0.42 3.03 0.991 B-Ar 4.09 2.45 0.984 -
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