ISSN:
1662-9752
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:
The effect of the concentration of Ni, Y and La-rich mischmetal on thethermal stability, microstructure and mechanical properties of ribbons tested in thetemperature range 25-350°C have been evaluated. The low-alloyed materials werecrystalline or partially crystalline while high-alloyed materials were amorphous. Theamorphous alloys experienced numerous transformations during heating above 170°C.A transition in the amorphous state was observed in all alloys prior to the crystallizationstage. The alloy composition determines the sequence of phase transformations duringcrystallization. In general, the structure of crystallised amorphous, even at hightemperatures, is much finer than that of crystalline materials. A MgxREy intermetallicmatrix with other intermetallic phases homogeneously distributed was observed in thecrystallised ribbons with high RE contents. However, a magnesium matrix embeddingother intermetallic phases was the microstructure observed for low-alloyed materials.The amorphous Mg-10Ni-2.5Y2.5-2.5La(MM) showed the higher tensile strengthvalues up to 200 ºC The crystalline Mg-2Ni-1Y-1La(MM) ribbon and the partiallycrystalline Mg-3Ni-1.5Y-1.5La(MM) alloy also exhibited high mechanical resistancelevels which were maintained up to 250 ºC. MgNi10Y2.5La(MM)2.5 amorphous andMgNi3Y1.5La(MM)1.5 crystalline broken above 500 and 400 MPa, respectively, at 100ºC
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/15/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.539-543.1662.pdf
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