LIU Yi,HE Hui,LIU Kefei,WU Qingding

(Research Institute of Material Foriming Technology，Central South University of Forestry and Technilogy，Changsha 410004，China)

Abstract: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·m^-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.

Keywords:poplar powder;poplar fiber;walnut shell granule;nacre-inspired composite;binderless warm-pressing compaction;response surface method;strengthening and toughening mechanism

中图分类号：S781.2；TB332                        文献标志码：A

文章编号：1008-5548(2022)05-0102-11

DOI:10.13732/j.issn.1008-5548.2022.05.013

收稿日期： 2022-03-04， 修回日期：2022-03-22，在线出版时间：2022-08-09 14:10。

基金项目：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。

第一作者简介：刘意(1998—)，男，硕士研究生，研究方向为生物质粉体材料成形理论与技术。E-mail：1004519486@qq.com。

通信作者简介：吴庆定(1963—)，男，教授，博士，博士生导师，研究方向为粉体材料成形理论与技术。E-mail：wudingle@126.com。