杨木-核桃壳仿贝壳复合材料的制备与强韧化机理  

Preparation and strengthening and toughening mechanisms of poplar-walnut shell nacre-inspired composite

作　　者：刘意 何惠 刘克非 吴庆定[1] LIU Yi;HE Hui;LIU Kefei;WU Qingding(Research Institute of Material Foriming Technology,Central South University of Forestry and Technilogy,Changsha 410004,China)

机构地区：[1]中南林业科技大学材料成形技术研究所,湖南长沙410004

出　　处：《中国粉体技术》2022年第5期102-112,共11页China Powder Science and Technology

基　　金：湖南省自然科学基金/常德市联合基金项目,编号:2020JJ6065;长沙市自然科学基金项目,编号:Kq2202275。

摘　　要：为了借助贝壳结构来获得高强韧化木质复合材料,以杨木粉末、杨木纤维和核桃壳颗粒为原料,不添加胶黏剂,采用温压成形法制备仿贝壳复合材料。通过单因素试验,优化仿贝壳复合材料中杨木粉末-核桃壳颗粒混合物与杨木纤维复合质量比;基于响应面法,优化仿贝壳复合材料工艺参数;运用傅立叶红外光谱仪、同步热分析仪、扫描电子显微镜对仿贝壳复合材料进行表征。结果表明:在杨木粉末-核桃壳颗粒混合物与杨木纤维复合质量比为6∶4、成形温度为162℃、成形压力为77 MPa、保温时间为25 min工艺条件下制备的仿贝壳复合材料的静曲强度和冲击韧性分别达到47.72 MPa、7.13 kJ·m^(-2),吸水率仅为3.39%,热稳定性好;仿贝壳复合材料通过裂纹偏转、裂纹桥接2种方式实现强韧化。In order to develop wood-based composite with high strength and toughness derived from shell structure,the nacre-inspired composite,without adhesive,was prepared by warm pressing process with poplar powder,poplar fiber and walnut shell granules.The mass ratio of poplar powder-walnut shell granules mixture to poplar fiber was optimized by single factor test.The process parameters were optimized by response surface method.Fourier transform infrared spectrometer,synchronous thermal analyzer and scanning electron microscope were used for characterization of nacre-inspired composite.The results show that under the mass ratio of 6∶4 of poplar powder-walnut shell granules mixture to poplar fiber,forming temperature of 162℃,forming pressure of 77 MPa and holding time of 25 min,the static bending strength and impact toughness of the nacre-inspired composite reache 47.72 MPa and 7.13 kJ·mm^(-2) respectively.At this time,the water absorption of the nacre-inspired composite is only 3.39%and the thermal stability is good.The nacre-inspired composite is strengthened and toughened through crack deflection and crack bridging.

关 键 词：杨木粉末 杨木纤维 核桃壳颗粒 仿贝壳复合材料 无胶温压成形 响应面法 强韧化机理 

分 类 号：S781.2[农业科学—木材科学与技术] TB332[农业科学—林学]