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Haddad, A.

Publications and source records attributed to Haddad, A..

Microstructure, Corrosion and Magnetic Behavior of an Aged Dual-Phase Stainless Steel

In the present work, the effect of the precipitation phenomena on corrosion and magnetic behavior of an aged dual-phase stainless steel was investigated. Aging treatment caused the precipitation of the σ phase, chromium carbides and secondary austenite, which was accompanied by the shifting of the δ/γ interfaces inside the δ ferrite grains. Aging between 700 and 850 °C strongly deteriorated the pitting corrosion resistance of the studied material. Magnetic investigation of the aged material using the vibration sample magnetic technique revealed the sensitivity of the intrinsic magnetic properties to the smallest microstructural change. This was confirmed by the Eddy current technique that led also to the evaluation of the aging-induced localized corrosion.

36 MATERIALS SCIENCE↗

New Diphosphopentamolybdate K{sub 5}[HP{sub 2}Mo{sub 5}O{sub 23}] · 10H{sub 2}O: Synthesis, Structure, and Characterization

A new diphosphopentamolybdate(VI) K{sub 5}[HP{sub 2}Mo{sub 5}O{sub 23}] · 10H{sub 2}O has been prepared employing solution method and characterized by single crystal X-ray diffraction, energy dispersive analysis, infrared spectroscopy, thermal stability analysis, cyclic voltammetry analysis, and ultraviolet visible spectroscopy. The compound crystallizes in the orthorhombic sp. gr. Pcab: a = 15.9661(10) Å, b = 19.0832(10) Å, c = 20.0970(9) Å, V = 6123.27(10) Å3, Z = 8. The crystal structure contains the polyanion units [HP{sub 2}Mo{sub 5}O{sub 23}]{sup 5–} around the potassium cations and lattice water. The [HP{sub 2}Mo{sub 5}O{sub 23}]{sup 5–} subunits are connected together through K−O−Mo bridges and hydrogen bonds. The crystal shape morphology was simulated using the Bravais–Friedel–Donnay–Harker model.

36 MATERIALS SCIENCE↗

Information science

Information processing techniques and systems reliability by coding, digital designed methods, retrieval, and communication

Ash, R. B.↗