摘要
用山毛榉薄木/酚醛树脂(PF)复合材料在常压下密闭隔氧烧结制备具有层状结构的木材陶瓷。用扫描电子显微镜(SEM)和X-射线衍射仪(XRD)对试件的结构和物相进行研究。SEM分析显示:木材陶瓷具有清晰的层状结构,保留了木材作为生物模板的天然特征。XRD的研究结果表明:提高烧结温度在改善木材陶瓷可石墨化程度的同时还能提高其纯度。烧结温度和树脂含量对层状木材陶瓷的力学性能和孔隙结构具有双重作用:抗弯强度在800℃之前迅速增加,在1200℃附近出现转折点;表观密度呈现出与此基本相同的现象;真密度随着烧结温度和树脂含量的增加而增加。层状木材陶瓷的断裂韧性为0.8～1.2MPa.m1/2,是采用常规方法制备的木材陶瓷的2倍多,且层状结构能够提高裂纹的扩展容限,避免破坏过程中的灾难性断裂。
Laminated woodceramics was made form beech veneer-formaldehyde phenol resin composite sintering at atmospheric pressure and airtight condition. Microstructure and phases composition were analyzed with scanning electron microscopy （SEM） and X-ray diffraction （XRD）. Results from SEM analysis showed that, woodceramics had clearly laminate structure and partly kept microstructure characteristics with native wood. XRD analysis indicated that, as increasing of sintering temperature, the graphitization degrees of laminated woodceramics had been improved and could make it more purer. Sintering temperature and PF resin content hand double effects on its mechanical properties and pore structure. Bending strength increased quickly before 800℃ and then decreased at 1200 ℃, apparent density had same result as this. True density increased with the increasing sintering temperature and PF resin contents. Fracture toughness of laminated woodceramics is 0.8 - 1.2 MPa·m^1/2 , which is two times of the ordinary woodceramics. The laminated structure will enlarge the expansion path, improve the crack tolerance greatly and can avoid calamitously rupture.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2009年第6期127-132,共6页
Scientia Silvae Sinicae
基金
湖南省科技攻关项目(2006FJ3127)
湖南省科技厅重点科技项目(2007TP4002)
关键词
木材陶瓷
层状结构
密闭烧结
特性表征
woodceramics
laminate structure
airtight sintering
characterization
