Effect of extrusion ratio on fatigue behaviour in Mg2Si- particulate reinforced magnesium alloy composites

被引：0
作者：
Department of Mechanical and Systems Engineering, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu, 501-1193, Japan [1 ]
机构：
[1] Department of Mechanical and Systems Engineering, Gifu University, Gifu-shi, Gifu, 501-1193
来源：
Nihon Kikai Gakkai Ronbunshu A | 2008年 / 3卷 / 459-466期
关键词：
Composite; Crack growth; Crack initiation; Extrusion ratio; Fatigue; Magnesium alloy; Mg[!sub]2[!/sub]Si;
D O I：
10.1299/kikaia.74.459
中图分类号：
学科分类号：
摘要：
This paper describes the effect of extrusion ratio on the fatigue behaviour of Mg2Si-particulate reinforced magnesium alloy composites produced with 2 mass% Mg2Si particles by powder metallurgy. The matrix magnesium alloy powders used were AZ61 and AZ80. Rotating bending fatigue tests have been performed using smooth specimens of materials extruded at three different extrusion ratios of 36, 67 and 133 at a low extrusion temperature. It was found that the extrusion ratio dependence of fatigue strength was different between two composites, Mg2Si/AZ61 and Mg2Si/AZ80. In the former composite, extrusion ratio exerted no significant influence on fatigue strength, while in the latter composite, there existed no discernible difference in fatigue strength between the materials extruded at the extrusion ratios of 36 and 67, but the material extruded at the extrusion ratio of 133 exhibited higher fatigue strength than those materials. Different crack initiation mechanisms operated depending on matrix alloy, extrusion ratio and applied stress level. In Mg2Si/AZ61, cracks initiated at Mg2Si particles regardless of extrusion ratio and applied stress level, while in Mg2Si/AZ 80, the same crack initiation mechanism as in Mg 2Si/AZ61 operated at the materials extruded at the extrusion ratios of 36 and 67, but cracks generated due to cyclic slip deformation of the matrix at low applied stresses in the material extruded at the extrusion ratio of 133. It was indicated that such crack initiation behaviour was the primary cause of the observed fatigue strength in the present composites.
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页码：459 / 466
页数：7
相关论文
共 8 条
  • [1] Tokaji K., Kamakura M., Ishiizumi Y., Hasegawa N., Fatigue Behaviour and Fracture Mechanism of a Rolled AZ31 Magnesium Alloy, International Journal of Fatigue, 26, pp. 1217-1224, (2004)
  • [2] Kamakura M., Tokaji K., Ishiizumi Y., Hasegawa N., Fatigue Behaviour and Fracture Mechanism of an Extruded AZ61 Magnesium Alloy, Journal of the Society of Materials Science, Japan, 53, 12, pp. 1371-1377, (2004)
  • [3] Kamakura M., Tokaji K., Uematsu Y., Microstructure and Fatigue Behaviour of Mg<sub>2</sub>Si- Dispersed Magnesium Alloys Produced by Solid-State Synthesis, Journal of the Society of Materials Science, Japan, 55, 1, pp. 55-60, (2006)
  • [4] Kamakura M., Tokaji K., Shibata H., Bekku N., Grain Refinement and Improvement of Fatigue Strengthdue to Controlled Extrusion in Magnesium Alloys, Journal of the Society of Materials Science, Japan, 54, 3, pp. 245-250, (2005)
  • [5] Uematsu Y., Tokaji K., Kamakura M., Uchida K., Shibata H., Bekku N., Effect of Extrusion Conditions on Grain Refinement and Fatigue Behaviour in Magnesium Alloys, Materials Science and Engineering, A434, pp. 131-140, (2006)
  • [6] Murai T., Matsuoka S., Miyamoto S., Oki Y., Effects of Extrusion Conditions on Microstructure and Mechanical Properties of AZ31B Magnesium Alloy Extrusions, Journal of Japan Institute of Light Metals, 51, 10, pp. 539-543, (2001)
  • [7] Chen Y., Wang Q., Peng J., Zhai C., Ding W., Effects of Extrusion Ratio on the Microstructure and Mechanical Properties of AZ31 Mg Alloy, Journal of Materials Processing Technology, 182, pp. 281-285, (2007)
  • [8] Garces G., Perez P., Adeva P., Effect of the Extrusion Texture on the Mechanical Behaviour of Mg-SiC<sub>p</sub> Composites, Scripta Materialia, 52, pp. 615-619, (2005)
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