The differential cross sections for the elastic scattering of neutrons by He have been measured at incident neutron energies of 17.6, 20.9, and 23.7 MeV for lab angles between 20 and 140'. The cross sections were measured relative to the~H(n, n)~H cross sections by the neutron time-of-flight technique. The 0.75-M He scattering sample was a liquid contained in a thin-walled cryostat. Corrections were made for multiple scattering and attenuation. Phaseshift analyses were performed using both differential-cross-section and polarization data. The present phase shifts are joined to the well-established low-energy phase shifts giving a smooth energy dependence.

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A mixture of TiO2, B2O3, and Al powders was reacted exo‐thermically to form a low‐density Al2O3–TiB2 foamed product. After the cessation of the combustion synthesis reaction, this hot foam was densified by the pressure waves generated by the detonation of an explosive charge. The delay time between the initiation of the combustion synthesis and detonation of the explosive, the thickness of the explosive charge, and the strength of sample confinement were found to influence the effectiveness of the consolidation. Analysis of the combustion synthesis reaction temperature histories and microscopy of the reacted product sponge are used to develop additional information about this reaction/consolidation process. These results, and the microstructural properties of the combustion‐synthesized and dynamically consolidated products, are discussed.

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