Aside from its economic value, davidite and its synthetic analogs may have potential applications in materials science. The unique properties of the crichtonite group minerals, including davidite-(La), make them attractive candidates for high-level waste (HLW) immobilization. We studied the thermal evolution of the metamict davidite-(La) from the Radium Hill, Australia. The investigation of the temperature-induced crystallization process was conducted, and the thermal expansion coefficients (TEC) for the recrystallized davidite (RD) were determined for the first time. Our results demonstrate that RD has relatively low TEC indicating its thermophysical stability. The following TECs of davidite- (La) for the temperature range 25–1200 °C were obtained: \(\overline{\mathrm{\alpha }}\) _a = \(\overline{\mathrm{\alpha }}\) _b = 9.96 (3) × 10^–6 ºC⁻¹; \(\overline{\mathrm{\alpha }}\) _c = 10.79 (4) × 10^–6 ºC⁻¹. The character of the thermal expansion is in agreement with the structure characterized by layers stacked along the c axis. The volume TEC α_V = 24.81 (47)—36.80 (48) × 10^–6 ºC⁻¹. Davidite-(La) exhibits an almost isotropic thermal expansion and shows one of the most superior thermal performances in comparison to the other mineral-like phases utilized for the immobilization of HLW.

除了其经济价值外，铁橄榄石及其合成类似物可能在材料科学中具有潜在的应用。方辉石族矿物（包括菱镁矿（La））的独特性质使其成为高放废物（HLW）固定化的有吸引力的候选者。我们研究了来自澳大利亚镭山的变晶戴维石 (La) 的热演化。对温度诱导结晶过程进行了研究，并首次测定了再结晶戴维石（RD）的热膨胀系数（TEC）。我们的结果表明 RD 的 TEC 相对较低，表明其热物理稳定性。获得了温度范围为 25–1200 °C 的菱铁矿 (La) 的以下 TEC：\(\overline{\mathrm{\alpha }}\) _a = \(\overline{\mathrm{\alpha }}\ ) _b  = 9.96 (3) × 10 ^–6  ℃ ⁻¹ ; \(\overline{\mathrm{\alpha }}\) _c  = 10.79 (4) × 10 ^–6 ºC ⁻¹。热膨胀的特征与沿c轴堆叠的结构特征一致。体积TEC α _V  = 24.81 (47)—36.80 (48) × 10 ^–6 ℃ ^-1。大卫石-(La) 表现出几乎各向同性的热膨胀，与用于固定 HLW 的其他类矿物相相比，显示出最优越的热性能之一。