高温热处理对木材强度影响的研究进展

从热处理方式、热处理工艺参数及影响强度机制等方面综述高温热处理对木材力学强度的影响。综合认为,不同热处理方式对木材强度影响程度不同。随着热处理温度升高和时间延长,抗弯强度和顺纹抗压强度等部分木材强度逐渐下降;但当处理温度较低时,抗弯弹性模量和表面硬度有所增加,随温度升高,其强度值将下降。不同热处理工艺对木材半纤维素、木素和纤维素定性变化规律是相同的。热处理过程与木材初始状态(含水率和干燥方式),以及热处理参数(温度和时间)交互作用对木材强度影响将是今后研究的方向之一。

Research progress in effect of heat treatment on wood strength

This paper reviewed the impact of high temperature heat treatment on the wood mechanical properties from heat treatment method,process parameters and influence mechanism.Through comparative analysis main conclusions could be drawn as follows: the wood strength was varified under different heat treatment method.The general trend for wood heat treatment was that,such as modulus of rupture(MOR) and compression strength parallel to the grain(CSPG) gradually decreased with the increase of the heat treatment temperature and time.At relatively low temperature heat treatment,modulus of elasticity(MOE) and hardness of the wood increased to some extent.As the treatment temperature continued to go up to a certain point,the strength of wood started to drop.In addition,seldom studies were conducted on the interactive effect of the heat treatment process,wood initial state(moisture content and drying method) and heat treatment parameters(temperature and time) on the wood strength.The hemi-cellulose,lignin and cellulose of wood changed following a similar profile under different heat treatment method.Based on the above analysis,some suggestions were proposed in this paper for future research work.