Catalytic degradation via fly ash impregnation (Im) has proven effective in reducing the heat modification (HM) temperature required for wood. To accurately gauge the intensity of HM on wood following Im, the physiomechanical properties of Im-HM treated wood were investigated across various treatment conditions (temperature: 80–140°C, duration: 1–4 h, and fly ash concentration: 2–8%), and compared them to conventional HM (CoHM) wood. Two mathematical methods (time-temperature superposition and cluster analysis) were employed to elucidate the relationships between treatment conditions and resulting properties. Results indicated that Im-HM treated wood exhibited comparable dimensional stability and visual appearance to CoHM wood, while retaining superior mechanical properties. The acid-catalyzed effect of Im-HM demonstrated significant dependence on treatment temperature, duration, and concentration, providing an avenue to regulate catalytic intensity. Employing the time-temperature superposition principle, master curves for weight percentage loss (WPL), modulus of elasticity (MOE) and anti-swelling efficiency (ASE) were constructed under a reference condition (80°C and 2% concentration), covering processing duration up to 20 hours. These master curves facilitated understanding the relationship between temperature, duration and concentration when evaluating catalytic intensity. Cluster analysis, based on the physiomechanical properties of Im-HM and CoHM wood, offered a clear interpretation of HM intensity. Notably, Im-HM treatment at 140°C for 4 hours with an 8% concentration exhibited HM intensity similar to CoHM treatment at 200°C. Through the integration of time-temperature superposition and cluster analysis, this study assesses Im-HM intensity, providing a valuable reference for the industrial application of Im-HM treatment.

中文翻译：

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粉煤灰浸渍提高杉木热改性效率：时温叠加与聚类分析综合评价

事实证明，通过飞灰浸渍 (Im) 进行催化降解可有效降低木材所需的热改性 (HM) 温度。为了准确测量 Im 处理后木材上 HM 的强度，在各种处理条件下研究了 Im-HM 处理过的木材的物理力学特性（温度：80–140°C，持续时间：1–4 小时，飞灰浓度：2– 8%），并将它们与传统的 HM (CoHM) 木材进行比较。采用两种数学方法（时间-温度叠加和聚类分析）来阐明处理条件和所得特性之间的关系。结果表明，经过 Im-HM 处理的木材表现出与 CoHM 木材相当的尺寸稳定性和视觉外观，同时保留了优异的机械性能。 Im-HM 的酸催化效果表现出对处理温度、持续时间和浓度的显着依赖性，为调节催化强度提供了途径。利用时间-温度叠加原理，在参考条件（80℃、2%浓度）下构建了失重率（WPL）、弹性模量（MOE）和抗膨胀效率（ASE）主曲线，涵盖加工过程持续时间长达20小时。这些主曲线有助于理解评估催化强度时温度、持续时间和浓度之间的关系。基于 Im-HM 和 CoHM 木材的物理力学特性的聚类分析为 HM 强度提供了清晰的解释。值得注意的是，在 140°C 下以 8% 浓度处理 4 小时的 Im-HM 表现出与在 200°C 下 CoHM 处理相似的 HM 强度。本研究通过时间-温度叠加和聚类分析相结合，评估Im-HM强度，为Im-HM处理的工业应用提供有价值的参考。