ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Recently, Mg-Zn-Y alloys with superior performance, which have a long period order(LPO) phase, have been developed. Therefore, it is important to understand fundamental fatigueproperties in such materials. In this study, the fatigue fracture behavior of Mg-Zn2-Y2-Zr0.2 alloy hasbeen investigated using a plain fatigue bending testing machine, which was originally developed forthin sheet specimen. One end of the sheet specimen is fixed at a voice coil of the loudspeaker andthe other end is set free. A bending mode resonance occurs in the specimen due to forced vibrationat the fixed end. To estimate stress amplitude of bending, deflections at the free end of the specimenoscillating at a frequency of about 250~700Hz was measured by a laser displacement gauge. Forcomparison, AZ31B alloy also has been investigated. S-N curve for the Mg-Zn2-Y2-Zr0.2 alloywas obtained using a stress ratio of R=-1, and the fatigue strength was estimated as about 200MPaat 106~108 cycles. The value corresponds to about 50% of 0.2% proof strength of the alloy. Twotypes of fatigue surface were observed in the alloy. One is striation like pattern and the other isrelatively flat surface. The former is similar to fatigue surface of AZ31B. Therefore, these two typesof fatigue surface correspond to crack passing through α-Mg phase and LPO phase, respectively
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.326-328.975.pdf
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