CONE CALORIMETER TESTS OF WOOD COMPOSITES

摘要

The cone calorimeter is widely used for the determination of the heat release rate (HRR) ofrnbuilding products and other materials. As part of an effort to increase the availability of conerncalorimeter data on wood products, the U.S. Forest Products Laboratory and the American WoodrnCouncil conducted this study on composite wood products in cooperation with the Composite PanelrnAssociation and APA-The Engineered Wood Association. We tested the specimens in accordancernwith ASTM E 1354 and used a heat flux of 50 kW/m~2. The twenty-nine commercial woodrncomposites included untreated and fire-retardant-treated (FRT) particleboards, untreated and FRTrnmedium density fiberboards, untreated high density fiberboards, untreated plywoods, and untreatedrnoriented strand boards. Such FRT composites are made to have a Class A flame spread rating whenrntested in the ASTM E 84 tunnel test. Fire retardant treatment of the wood products reduced the initialrnHRR, reduced the mass loss rate, increased the residual mass fraction, resulted in lower averagerneffective heat of combustion values, and usually resulted in longer ignition times. For the untreatedrnspecimens, the results for residual mass fraction at the end of the test ranged from 0.13 to 0.28 with arnmean result of 0.23. In contrast, the results for the FRT samples ranged from 0.33 to 0.39 with a meanrnresult of 0.36. In the case of the 300 s HRR averages, the range was 118 to 218 kW/m~2 for thernuntreated composites and 58 to 100 Kw/m~2 for the FRT composites.