April 17, 2017 05:42 PM

Zirconium has a low neutron cross section and high degree of corrosion resistance. It is widely used in industry and engineering, in particular in the area of refractory applications. Knowledge of elastic and thermal properties of zirconium is important for understanding the behavior and performance of the materials at extreme conditions. By combining X-ray diffraction and X-ray imaging techniques, together with ultrasonic wave velocity measurements, in a Paris-Edinburgh press at HPCAT, a research team has determined multiple elastic and thermal properties including bulk modulus, shear modulus, Poisson’s ratio, and Debye temperature at high pressure and high temperature conditions.    More...

March 14, 2017 02:55 PM

It has been predicted that hydrogen-rich material may promote metallization of hydrogen through chemical pressure imposed by the foreign atoms or molecules. A group utilizing HPCAT’s facility studied a hydrogen rich compound, Ar(H2)2, to ultrahigh pressures over three megabars.  More...

March 13, 2017 06:45 PM

As an archetypal semimetal with complex and anisotropic Fermi surface and unusual electric properties (e.g., high electrical resistance, large magnetoresistance, and giant Hall effect), bismuth (Bi) has played a critical role in metal physics. For over a century, Bi has been known to be diamagnetic. A research team observed unusual ferromagnetism in bulk Bi samples recovered from a molten state at pressures of 1.4–2.5 GPa and temperatures above 1,250 K.  More...

March 9, 2017 05:32 PM

Meteorites preserve evidence of processes ranging from the formation of the solar system to the origin of life on Earth and the potential for extraterrestrial habitability. One mineral of particular interest in meteorites is the phosphate mineral merrillite, an anhydrous end-member of the merrillite–whitlockite solid solution series, with whitlockite being the hydrogenated end member. Recent experimental observations...  More...

March 2, 2017 12:27 PM

High-pressure melting anchors the phase diagram of a material, revealing the effect of pressure on the breakdown of the ordering of atoms in the solid. An important case is molybdenum (Mo), which has long been speculated to undergo an exceptionally steep increase in melting temperature when compressed.  Recent HPCAT experiments found a high-slope melting curve in Mo.  More...