A quantitative interpretation of DSC experiments on quenched and aged SiC{sub P} reinforced 8090 alloys
- Univ. of Southampton (United Kingdom). Dept. of Engineering Materials
Differential Scanning Calorimetry (DSC) is a useful technique for the study of phase transformations and has been widely applied to study precipitation in aluminum alloys, but the results are generally interpreted qualitatively. In the present paper a quantitative interpretation of DSC heat effects occurring in 8090 alloys with and without SiC particle reinforcement is presented. Hardening of 8090 alloys (nominal composition Al-1.3wt% Cu-1wt%Mg-2.5wt%Li) is generally interpreted in terms of two precipitation sequences: (1) Li in Al-rich phase {yields} {delta}{prime} {yields} {delta}, where {delta}{prime} is a L1{sub 2} ordered phase (Al{sub 3}Li), fully coherent with the Al matrix, and {delta} is the equilibrium Al-Li phase (AlLi), which forms mainly at grain boundaries; (2) Cu,Mg in Al-rich phase {yields} GPB zones {yields} S{prime} {yields} S, where GPB zones are Cu and Mg containing Guinier-Preston zones, and S{prime} is a slightly strained semicoherent version of the incoherent S (Al{sub 2}CuMg). Since the formation enthalpies of the two variants are the same, S{prime} and S will be considered to be the same phase in this paper.
- OSTI ID:
- 237848
- Journal Information:
- Scripta Metallurgica et Materialia, Journal Name: Scripta Metallurgica et Materialia Journal Issue: 6 Vol. 33; ISSN SCRMEX; ISSN 0956-716X
- Country of Publication:
- United States
- Language:
- English
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