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Abstract: The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for the hydride precipitation, and the large concentration of lattice defects induced by HPT was considered to be responsible for this enhanced susceptibility. [Copyright &y& Elsevier]

Abstract: Perovskite 0.4Bi(Zn1/2Ti1/2)O3–0.6PbTiO3 (BZT–PT) powders were successfully synthesized from precursor oxides using a high-energy planetary ball milling. The phase development of the powders during milling was studied by means of X-ray diffraction and Raman scattering techniques. The microstructure of the powders was characterized using transmission electron microscopy, and the thermal behavior was studied as well. The results reveal that after 15 h of milling the formation of BZT–PT phase can be completed and submicron agglomerates of small crystallite sized ~12 nm are present in the powders. However, further prolonging the milling time to 25 h leads to the amorphization of the BZT–PT phase. [Copyright &y& Elsevier]

Abstract: The selective laser melting (SLM) of the TiH2–Ti blended powder was performed in the present work. Porous titanium scaffolds characterized by high porosity (∼70%), interconnected Ti walls and open porous structures with macroscopic pores (in a range of ∼200 to ∼500μm) were successfully prepared at a laser power of 1000W and a scan speed of 0.02m/s. The effects of componential and processing conditions in terms of TiH2 content and scan speed on the microstructural development of porous titanium (porosity and pores size) were investigated. Reasonable mechanisms for pores formation during SLM apart from microstructural evolutions were proposed. [Copyright &y& Elsevier]