Investigation into the Performance Enhancement of Calcium Phosphate Mineralization-Compacted Chinese Fir

Abstract

The utilization of wood as a construction material offers inherent advantages, including its renewability, good process property, wide availability, and carbon sequestration. However, its susceptibility to combustion and limited mechanical properties also constrain its applications. In this work, calcium phosphate was in situ deposited in dignified Chinese fir wood, followed by hot-pressed densification. Thermogravimetric analysis (TG) reveals that mineralization and densification alleviate the thermal decomposition and combustion behavior of wood, which greatly promotes the formation of the dense char layer during wood combustion. Therefore, the maximum heat release rate (HRR), total heat release rate (THR), and total smoke production rate (TSP) of the as-prepared mineralized dense wood were significantly reduced by 37%, 32%, and 56% compared with the control one. Further, the mineralized dense wood showed a remarkable enhancement in flexural strength and flexural modulus of elasticity, 203% and 220% higher than the natural wood, respectively. This study demonstrated a straightforward and eco-friendly approach to fabricating structural wood possessing exceptional flame retardancy and mechanical characterization, which holds immense potential for application in energy-efficient green buildings.