Effect of Pre-Strain on Fatigue Behaviour of AZ31 Mg Alloy

Abstract:

Mg Alloys Are the Lightest Structural Alloys with Excellent Castability and Machinability as Well as Highest Specific Strength and Stiffness. According to their Hexagonal close Packed Crystal Lattice there Is an Urgent Requirement of Mechanical Property Evaluation Method for Industrial Application, Particularly to Wrought Mg Alloys. Cyclic Loading Is a Very Popular Mode for Most Structural Application Situations. Recent Development of Fatigue Examination of Extruded Profile Has Shown that Mg Alloys Show Not so Ideal Fatigue Property. so that the Further Detailed Study on Cyclic Loading for Plastic Deformed Mg Alloys Is Needed. Tension-Tension Fatigue Tests Were Conducted on Pre-Strained AZ31 Mg Alloys that Produced by Rolling and Extruding Procedures. the Results Show that the Compressive Plastic Deformation Leads to Reduction of Fatigue Life/limit Significantly. SEM Analysis on Fatigue Fracture Surfaces Indicates that the Fatigue Cracks Initiate in the Surface or Sub-Surface of Dramatically Deformed Zones. the Microstructure Analysis Reveals that the Pre-Strain Brings More Abundant Twinning Bands with the Increase in Pre-Strain. the Decrease in Fatigue Life Demonstrates Also some Critical Feature with the Pre-Strain Level.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 3052-3056
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.3052
• Online since: January 2012
• Authors: Gao Feng Quan, Ying Bo Zhang, Zhao Ming Liu
• Keywords: Fatigue Life, Magnesium Alloy AZ31, Pre-Strain, Twinned Bands

References

[1] Ishihara S., Nan Z., Goshima T., Mater. Sci. Eng., A 468 (2007) 214‐22.

[2] Zhang P., Lindemann J., Scripta Mater., 52 (2005) 1011‐1015.

[3] S.M. Yin, H.J. Yang, S.X. Li, S.D. Wu, F. Yang, Scripta Mater. 58 (2008) 751-754.

[3] Keiro Tokaji, Masaki Nakajima, Yoshihiko Uematsu, Inter'l J. Fatigue 31 (2009) 1137–1143.

[4] Gaofeng Quan, The Mechanical Behavior of Materials X，Key Eng. Mater. 2007，Vols. 345346, p.717720.

[5] Gaofeng Quan , Liming Cai, Materials Science Forum，Vols. 539-543 (2007) pp.1669-1674.

[6] Yang F., Yin S.M., Li S.X., Zhang Z.F., Mater. Sci. Eng., A, 491(2008)131-136.