ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Lead-base particulate composites, namely Pb-5 vol% Zn, Pb-5 vol% Al2O3 and Pb-2.5 wt% PbO have been prepared using powders of lead (atomized), zinc (atomized) and Al2O3 by a powder metallurgy technique followed by deformation processing. Isothermal creep tests have been performed at 100, 150 and 180° C on the recrystallized composites. Internal stresses in the steady-state region have been measured in a Pb-PbO composite to evaluate rate controlling mechanisms. Threshold stress for steady-state creep is observed in P/M lead and Pb-Al2O3 composites at 100 and 150° C, whereas it is absent in Pb-Zn composites. Two distinct stress exponent regions with different activation energies associated with them, are observed over a shear strain rate range of 10−7 to 10−4 sec−1. In the low stress exponent region, grain boundary sliding appears to be the rate controlling mechanism, whereas climb controlled dislocation creep is the operative mechanism in the other region.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00543819
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