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:
According to the characteristic of appearing cavitation in the metals during superplasticdeformation, the influence of strain rate on cavity evolvement, the influence of cavity on superplasticdeformation capability, and the formation, development process of cavity were investigated forAl-Cu-Mg alloy (i.e. coarse–grained LY12). The results show that: ①The pore nucleation occurs notonly at triangle grain boundaries, but also along nearby the second phase particles, and even withingrains. The cavities at the triangle grain boundaries are present in V-shape, others near the secondphase particles and within grains are present in O-shape. These cavities may result from disharmonyslippage of grain boundaries. ②The tendency of cavity development decreases with increasing ofstrain-rate. In lower strain-rate condition, though Al-Cu-Mg alloy has better superplasticity, many bigcavities in the specimen may reduce the room temperature properties of the alloy. In higher strain-ratecondition, Al-Cu-Mg alloy has certain superplasticity and room temperature properties as well as fewcavities forming. By analyzing, viscous layer on grain boundaries is very thin and grain sizes can berefined during their extruding and rotating each other in higher strain-rate superplastic deformationcondition. ③Growth and coalescence of cavity are the main reason of the superplastic fracture ofAl-Cu-Mg alloy. And small and a certain amount of cavities with dispersion and independence stateare very useful to crystal boundary slippage
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/16/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.551-552.645.pdf
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