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Commercially available titanium alloys as well as emerging titanium alloys with limited or no production experience are being considered for a variety of applications to high speed commercial aircraft structures. A number of government and industry programs are underway to improve the performance of promising alloys by chemistry andor processing modifications and to identify appropriate alloys and processes for specific aircraft structural applications. This paper discusses some of the results on the effects of heat treatment, service temperatures from -54 "C to +177 "C, and selected processing on the mechanical properties of several candidate beta and alpha-beta titanium alloys. Included are beta alloys Timetal 21S, LCB, Beta C, Beta CEZ, and Ti-10-2-3 and alpha-beta alloys Ti-62222, Ti-6242S, Timetal 550, Ti-62S, SP-700, and Corona-X. The emphasis is on properties of rolled sheet product form and on the superplastic properties and processing of the materials.

The core-level photoexcitation and photoionization of SF6 were studied in the vicinity of the resonances below and above the S 2p threshold. The decay channels of the S 2p→6a1g discrete excitation were characterized, with decay leading mostly to valence-shell satellites. The S 2p continuum data show an oscillatory asymmetry parameter β(S 2p) near threshold that is virtually identical to β(Si 2p) in SiF4. It also resembles—but differs from—theoretical curves for β(S 2p) in atomic sulfur and in SF6. Data at the feature assigned as an eg shape resonance indicate strong multielectron properties for this state, because a resonance in the S 2p satellite is observed at the same photon energy as the main-line resonance. We propose a unified model which generally includes configuration interaction both in the continuum-state manifold and between discrete doubly excited states and the continua, to explain this unexpected satellite behavior. Finally, the S(L2,3VV) Auger electron asymmetry parameter shows no significant deviation from zero near the t2g and eg shape resonances.