Keywords: 
• wood science and technology /
• immersion and compression /
• densified /
• cone /
• fire retardant /
• Cunninghamia lanceolata （Chinese fir）

Abstract: For efficient utilizing of fast-growing Chinese fir, make it to densified Chinese fir（Cunninghamia lanceolata） which immersion by phenolic resin and followed by compression. Using a cone calorimeter to test the combustion characteristics of densified Chinese fir, studying on combustion performance like heat release rate, total heat release, smoke production rate, total smoke rate, CO yield, effective heat of combustion, and mass loss rate with EN ISO5660-1. Results showed that densified Chinese fir after increasing density, the total heat released reached 160.98 kWm-2, and afterward this peak decreased quickly with no peak heat release after 20 s. But non-densified Chinese firs second peak heat release appeared at 400 s. The heat release rate, total smoke rate, and effective heat of combustion for densified Chinese fir were all lower than non-densified. Smoke production with the non-densified material had a second peak at 300 s and lasted about 100 s; however, densified Chinese firs second smoke production peak was delayed 6 minutes. For densified Chinese fir the total smoke rate was also postponed and reduced; whereas the peak CO yield was delayed 70 s. Additionally, sustained release time of densified Chinese fir decreased from 60 s of the non-densified material to 35 s and then declined rapidly. Thus, Chinese fir after densified showed excellent combustion properties. ［Ch, 9 fig. 11 ref.］