高频真空联合干燥具有高频快速加热及真空下水的沸点降低的双重优势，能够实现木材低温快速干燥，在大尺寸及名贵木材的干燥领域具有明显的优势。红木家具及工艺制品具有很高的经济和文化价值，但常规干燥由于温度高、周期长，容易导致红木变色、变脆及开裂等缺陷，严重影响了红木制品的质量。笔者在相同温度条件下对3种红木薄板进行高频真空干燥和常规干燥，对比分析了干燥后红木薄板的含水率分布、开裂、变色及干燥速度。试验结果表明：经过高频真空干燥的红木质量能达到国标二级，平均含水率达到家具及木制品生产工艺要求，颜色变化小，干燥速度快，尤其在高含水率范围内干燥速度更快。高频真空干燥能够提高红木薄板的干燥速度、干燥质量和效率，是红木材料干燥的优良方法。%Rosewood is widely accepted by consumers as one of the most desirable materials in high valued wooden products due to its properties, wood culture and sense of touch. High valued rosewood furniture and crafts are wide⁃spread in China. However, the defects such as discoloration, crisp and cracks occurred during conventional kiln ( CK) drying due to its high density and tight structure limit its utilization. Furthermore, the long CK drying periods also cause problems for the rosewood furniture manufacturing. Therefore, to obtain high drying quality of rosewood in short time, a new drying technology, radio⁃frequency/vacuum ( RF/V) , was introduced to the wood⁃drying industry. The RF/V drying combined with fast radio⁃frequency heating and low boiling point of water under vacuum conditions, which can dry wood with high rate and high quality. It has significant advantages for the drying of large dimension or high valued wood. In this study, to solve the drying defects resulted from the conventional kiln drying, RF/V and CK drying devices was used. Three rosewood species ( Pterocarpus macrocarpus, Dalbergia latifolia, Dal⁃bergia bariensis) were dried at the same temperature with RF/V and CK schedules. The wood quality such as the final moisture contents ( MC) distributions, cracks, discoloration, as well as the drying rate after drying were compared. The results showed that there were no cracks on ends, surface and inner of boards, the MC was even for all boards and the wood quality after the RF/V drying can meet the requirements of the grade 2 of GB/T 6491-2012. The aver⁃age moisture content after the drying can meet the requirements of furniture factories and crafts manufacturers. The dis⁃coloration of RF/V was less compared with that of CK drying because of rare air in the drying chamber. The drying rate of RF/V was faster compared with that of CK drying due to the easy moisture moving resulted from the fast RF heating and low chamber pressure. The RF/V drying can improve drying rate, drying quality and efficiency for the dr⁃ying of rosewood thin boards, which is an effective method for the drying of high valued species of rosewood.
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