Pore space of steatite ceramics triggered by the allowance of natural fibers: High-resolution X-ray microscopy analysis and related thermo-mechanical properties

Screening of Filler Material for a Packed‐Bed Thermocline Energy Storage Test Facility with Lead–Bismuth Eutectic as the Heat Transfer Fluid

“…The composition of the material investigated is shown in Table 7 and given by the supplier (CeramTec GmbH) according to DIN standard for C220 with a maximum of 64 wt% SiO 2 , a maximum of 31 wt% MgO and 4 wt% Al 2 O 3 , 1.4 wt% Fe 2 O 3 , and 1.2 wt% Na 2 O + K 2 O. [ 55 ] Steatite consists of a crystalline phase (70–80%) and an embedded glassy phase (20–30%) at room temperature, [ 56 ] as shown in Figure 13 , where the crystal structure appears brighter than the glassy phase (referred to as “glassy phase 1”). The composition of the small and bright particles on the surface is difficult to be determined by EDS due to their small size and is, therefore, strongly error prone, which is also reflected in the large standard deviation of the measurements.…”

Porous Talcum-Based Steatite Ceramics Fabricated by the Admixture of Organic Particles: Experimental Characterization and Effective Medium/Field Modeling of Thermo-Mechanical Properties

“…The resulting TBS ceramic is composed of proto- and clinoenstatite crystals (Mg Si O ), i.e., pyroxenes, and a small amount of cristobalite, all embedded in a barium containing glassy phase. As described in detail in [ 9 ], XRD gave access to the crystalline mineral phases of the material (see Table 2 , listing mass fractions related to the sum of crystalline phases only), with enstatite as the main phase. Additionally, a glassy phase, serving as a matrix in the material system, is present with a mass fraction of approximately 30 m% (related to total mass).…”

“…Recent, further applications were suggested in nuclear power applications [ 6 ] and medical engineering [ 7 , 8 ]. Recently, we described the synthesizing of a low-to-medium porosity talcum-based steatite (TBS) ceramic including a detailed pore space characterization and analysis of solid phase microstructure and composition [ 9 ]. Ceramic materials of this type are frequently denoted as steatite or steatite ceramic in the open literature.…”

“…Hence, the denomination “talcum-based steatite (TBS) ceramic” is chosen in this paper. [ 9 ] also contains a detailed description of the pore-forming agent—almond shell granulate—that has been intermixed within the green bodies prior to compaction and sintering. The so-obtained artificially introduced porosity may foster novel applications of the well-established ceramic material, as thermo-mechanical properties may be tailored to customer’s specifications.…”

“…The current paper focuses on the experimental characterization and discusses microstructure-based modeling of thermo-mechanical properties: heat capacity, thermal conductivity, Young’s modulus, and tensile (bending) strength of prism-shaped and plate-shaped specimens (obtained by cutting off from these prisms), respectively, of the porous TBS ceramic samples investigated in [ 9 ]. Thereby, Youngs’s modulus and bending (tensile) strength were determined from three-point bending experiments; in addition, elastic behavior was also assessed by ultrasonic compressive wave speed measurements in the longitudinal direction of the prisms.…”