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Creep in copper dispersion strengthened with fine alumina particles and reinforced with alumina short fibres—an ODS copper matrix composite

“…The σ TH decreases with increasing temperature more strongly than the shear modulus G of copper. In fact, the σ TH /G ratio decreases from 8.377×10 −3 to 5.133×10 −3 in LTI and from 1.867 × 10 −4 to 1.183 × 10 −4 in HTI (for G = G(T) see [2]). …”

“…Fabrication of the composite was described in detail elsewhere [1]. The volume fraction of alumina particles of ∼8.5 nm in diameter was close to 0.014, the volume fraction of alumina short fibres was nominally 0.15.…”

Nanoquasicrystalline Al–Fe–Cr-based alloys. Part II. Mechanical properties

“…The stress sensitivity parameter, n, is defined as the increment of stresses needed to cause a movement in the deformation strain rate of a certain material at a certain temperature and a given structure [6]. Based on this definition, the literature distinguishes between the n corresponding to a creep model related with a specific deformation mechanism and the apparent stress sensitivity parameter, n app , which is experimentally obtained from creep curves [7]. In the present work, and as a consequence of the anal- Table 1 Identification code, nominal chemical compositions and corrected nominal compositions of the master alloys used.…”

“…where n app is the apparent sensitivity parameter, r is the steady-state stress and R is the universal gas constant [6,7]. Therefore, empirically the apparent activation energy can be obtained from the slope of the curve of the natural logarithm of the true steady-state stress values as a function of 1/T.…”

“…No further studies on the mechanical properties and strengthening mechanisms at elevated temperature on this kind of alloys have been found in the open scientific literature. In an accompanying paper we report a detailed study of the microstructural evolution with the temperature of meltspun Al 93 (Fe 3 Cr 2 ) 7 and Al 93 Fe 3 Cr 2 (Ti, V, Nb or Ta) 2 alloys [5]. The main microstructural features in these alloys were the a-Al matrix and the icosahedral particles.…”