Solid-liquid phase equilibria of Fe-Cr-Al alloys and spinels

In‐situ determination of the HfO2–Ta2O5‐temperature phase diagram up to 3000°C

“…Cooling profiles on recalescence of the hafnium tantalate beads in air were recorded and analyzed. Selected beads were levitated and rotated in a conical nozzle levitator (CNL) in air, while being heated with a laser.…”

“…Selected beads were levitated and rotated in a conical nozzle levitator (CNL) in air, while being heated with a laser. This method has been described in more detail by McMurray et al and Ushakov . Temperatures on laser melting and cooling traces during quenching from the liquid state were simultaneously monitored using two pyrometers.…”

“…Due to these factors, in‐situ at temperature experiments will be used to elucidate high temperature (3000°C) HfO 2 –Ta 2 O 5 ‐temperature phase space accurately and efficiently. The two key experiments performed are as follows: (a) Thermal arrest measurements using a conical nozzle levitator (CNL) system equipped with a 400 W CO 2 laser and (b) in‐situ X‐ray powder diffraction (XRPD) in conjunction with the quadrupole lamp furnace (QLF) and CNL equipped with 400 W CO 2 laser systems . The thermal arrest experiments will determine the liquidus, solidus and invariant transformation temperatures while the in‐situ XRPD will allow for equilibrium phase identification, verification of transformation reversibility and measurements of the molar volume (thermodynamic parameter ∂G / ∂P = V ) as a function of temperature and composition via Rietveld refinement .…”

Steam Oxidation, Burst and Critical Heat Flux Testing of FeCrAl Cladding in the Severe Accident Test Station

“…An ATF cladding would significantly reduce the rate of heat and hydrogen generation in the core during a coolant-limited severe accident [16][17][18]. In the search for materials with steam oxidation rates that are 100× slower than current Zr-based alloys at ≥1200°C, FeCrAl alloys quickly became the focus of research at ORNL including alloy development [8], physical properties [9,10,[12][13][14][19][20][21][22][23] and integral data [24][25][26][27] to populate models [28][29][30][31][32].…”

Handbook of the Materials Properties of FeCrAl Alloys For Nuclear Power Production Applications

“…Figure 14b provides a bubble plot of the ORNL model alloys and Kanthal APMT tested in this manner, the dashed line is the same boundary plotted in the sister Figure 14a plot. Kanthal APMT is again used as the litmus test as the alloy's max use temperature is 1500°C, which is nearly the typical melting point for FeCrAl alloys [80]. The tests show alloys which have Cr and Al contents below the arbitrary line for protective oxidation, derived from the data in Figure 14a, tend to show poor performance with maximum use temperatures at or greatly below 1200°C.…”