小径柞木真空干燥应力的试验研究

在真空干燥条件下,分析小径级柞木板材的应力与含水率、时间的关系,结果表明:在低温条件下,由于真空负压作用,水分蒸发速度得到了加快,干燥应力由于干燥前板材内的初始应力的差异,导致干燥过程中应力的发生、发展有所差异。根据应力表现的差异应当在干燥不同阶段及时进行调湿处理,预防板材开裂产生。

The experimental study on vacuum drying stress of small diameter oak

Under the vacuum drying condition,the relationships between drying stress and water percentage and time of oak sheet with small diameter were measured.Results showed that under low temperature,the drying stress of oak sheet changed during the drying process.This change was resulted by the difference of initial stress before drying,which was enhanced by the high water evaporation rate due to the effect of negative pressure under vacuum condition.Suitable humidifying treatment should be applied according to the various stress,to prevent the cracking of sheet.