Effect of PostHeat Treatment on Dimensional Stability of Compressed Wood

The timber of Pinus armandii and Alnus cremastogyne was experimented to evaluate the dimensional stability by taking thickness swelling (TS) as the major evaluation index after the compressed wood was individually treated under 170℃ and 210℃ for 2h with the heated air or conductive oil heat transfer media. The results showed that both of the moistureuptake and wateruptake of the compressed wood could be reduced by post heattreating, so the dimensional stability of the compressed wood was improved. The conductive oil treatment had better effect than that of the hot air, while the treatment effect under 210℃ was better than that of under 170℃. The best technological condition was conductive oil treatment under 210℃, which could reduce moisture uptake TS index by 50% while reduce TS value after 24h water uptake by 85%. The results also showed that the effect of heat treatment varied with tree species, The heat treatment effect on Pinus armandii wood was better than that of on Alnus cremastogyne wood.