【目的】对比测试不同木材加工形态样本的的锥形量热( CONE)热释放特性参数，探究不同木材试样形态对 CONE热释放特性参数的影响规律和作用机制，为 CONE 热释放特性参数选择、材料燃烧过程评估以及阻燃机制研究提供依据。【方法】在50 kW·m －2热辐照功率下，通过 CONE 测定7种加工方式和形态不同杨木试样的热释放速率( HRR)及其峰值( PHRR)、总热释放量( THR)、有效燃烧热( EHC)等 CONE 热释放特性参数。【结果】通过分析不同木材试样热释放特性参数试验值的算术平均误差(ΔX)、相对误差( Er )和标准偏差( S)可知，在PHRR，MHRR，THR和 MEHC 4个热释放特性参数测定结果中，平均有效燃烧热( MEHC)的误差估算值最小，而PHRR的误差估算值最大；粉状试样的PHRR，MHRR，THR，MEHC 4个热释放特性参数试验值的误差估算值远小于板状试样的误差估算值，如PP，FPP 2个粉状试样的MHRR试验值的标准偏差( SMHRR )分别为1.2和1.1 kW·m －2，远低于其他5种标准板状试样，约为 SMHRR最大的 PPB的1/8。【结论】4个热释放特性参数中，MEHC 主要受燃烧状态影响，而 PHRR除了与燃烧过程有关外，还受试样自身和外界因素的影响。粉状试样热释放特性参数试验值的精密度优于板状试样，重现性好、可靠性高，完全适用于实验室内部测试和材料配方筛选等各种科学研究，可减少制备标准试样所需的材料和时间，为简化 CONE试验试样制作工艺提供了科学依据。%Objective]Cone calorimeter sample shape and size affect its experimental results. In order to clarify whether the powder samples are appropriate for CONE tests or not,seven different forms of wood samples were investigated by cone calorimeter. Study on the influence of sample shape and size on cone heat release parameters have important significance on selecting heat release parameters, evaluating combustion process and researching flame retardant mechanism.[Method]Seven different processing methods and forms of wood samples were investigated by cone calorimeter under a heat flux of 50 kW·m -2 . The PHRR ( peak of heat release rate ) ,HRR ( heat release rate ) ,THR ( total heat release) ,EHC( effective heat combustion) results were measured.[Result]Through analyzing the arithmetical mean error (ΔX),relative error(Er)and standard deviation(S)of the cone calorimeter results from seven types of wood samples,it was found that the error estimate of MEHC( mean of effective heat combustion) was the minimum and the error estimate of PHRR was the maximum in PHRR,MHRR,THR,MEHC four thermal parameters determination results. And the above-mentioned four heat release parameters of powder samples had low error estimates,far less than those of the plate samples. Such as two powdery samples of PP and FPP,their SMHRR respectively are 1. 2 and 1. 1 kW·m -2 respectively,which was about 1/8 of PPB and far lower than values of five plate samples.[Conclusion]The experimental results show that MEHC is mainly influenced by the combustion process,while the PHRR is influenced by the combustion state,sample itself and the external factors. Furthermore,the precision of the powdery samples is better than that of the plate samples,being with good reproducibility and high reliability. Therefore,powdery samples is suitable to be used in laboratory test and materials selection in scientific research,which can save the materials and time prepare the standard samples,and provide scientific basis to simplify the experimental sample of cone processing technology.
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