油茶果壳碎料板制造工艺及其性能研究

开展油茶果壳碎料板原材料资源化利用,既有益于促进我国油茶产业的可持续发展,又可提高经济效益。本研究采用全因子试验法探讨了胶粘剂种类、碎料形态及碱处理对油茶果壳碎料板物理力学性能的影响。实验结果表明:其产品抗弯弹性模量和静曲强度未达到国家普通刨花板的标准要求。为了充分利用油茶果壳作为复合材料原料,旨在缓解森林资源匮乏的现状,构建资源节约型、环境友好型社会,将来的研究可以进一步考虑利用油茶果壳质轻的特点制备力学强度要求不高的轻质刨花板。     

定向刨花板弹性模量理论分析的试验验证

介绍了定向刨花板的试验方法和过程；并应用概率设计理论求出了定向刨花板主方向的弹性模量，对定向刨花板产品进行了试验研究并与实验室产品进行了分析比较；分析了影响定向刨花板产品质量的主要因素。解决了定向刨花板弹性模量的理论求解公式的实验验证问题，论证了理论推导结果的正确性，尝试将现代设计方法和微观力学理论应用于人造板的力学性能分析和研究中，以推动定向刨花板的计算机仿真工作的开展。     

广宁县竹香骨下脚料制备竹碎料刨花板及其复合改性研究

采用竹香骨下脚料为原料,以脲醛树脂和三聚氰胺改性脲醛树脂胶粘剂制备竹碎料刨花板,并与木纤维复合改性,检测并分析了内结合强度、静曲强度、弹性模量和吸水性。结果表明,在热压温度为160℃时,竹碎料板和竹木复合碎料板的物理力学性能均满足国标规定在干燥状态下使用的普通用板要求。当木纤维与竹碎料复合后,复合板材的静曲强度和弹性模量有一定程度提高,但内结合强度降低。     

重组木复合刨花板截面最佳等强度的优化设计

以重组木复合刨花板微观力学的力泞 基础，应用材料力学的理论，以重组木复合刨菜板纵横向弹性模量与树种木材的差异最小为目标函数，并以重组木木束与刨花板刨花的相和学参数为优化变量，确定了重组木复合刨花板在满足最近似于实木性能条件下的最佳力学性能。本文所述的理论和方法为人造板复合材的优化设计提供了实用的理论和方法，也为人造板力学提供了基本理论和优化的方法。     

定向刨花板强性模量理论分析的试验验证

介绍了定向刨花板的试验方法和过程;并应用概率设计理论求出了定向刨花板主方向的弹性模量,对定向刨花板产品进行了试验研究并与实验室产品进行了分析比较;分析了影响定向刨花板产品质量的主要因素.解决了定向刨花板弹性模量的理论求解公式的实验验证问题,论证了理论推导结果的正确性.尝试将现代设计方法和微观力学理论应用于人造板的力学性能分析和研究中,以推动定向刨花板的计算机仿真工作的开展.     

竹碎料含水率对无胶竹木复合夹层板性能的影响

以竹碎料为芯层材料,以杨木单板为表板材料制备无胶竹木复合夹层板,研究芯层竹碎料含水率对夹层板各种性能指标的影响规律。结果表明:芯层竹碎料含水率对无胶竹木复合夹层板的内结合强度、表面胶合强度、吸水厚度膨胀率的影响显著,而对静曲强度和弹性模量的影响不显著。综合考虑各种性能指标,确定芯层竹碎料的含水率为18%左右制备的无胶竹木复合夹层板的性能较优,并且达到室内干燥状态下使用的普通刨花板的用板要求。     

芦苇-稻草原料球磨处理生产刨花板

选择芦苇和稻草为原料,以脲醛树脂为黏结剂制备了芦苇-稻草刨花板。在芦苇碎料中加入一定量的矿物材料,然后采用机械球磨进行处理,应用正交设计对施胶量、热压压力、碎料球磨处理3个因素对板材各项性能的影响进行了研究。实验结果表明,球磨处理可以明显改善芦苇／树脂的结合强度,提高刨花板的各项性能。在施胶量16％,热压压力3．4MPa,对碎料进行球磨处理后制板,除内结合力较低外,板的静曲强度、弹性模量和握钉力都可以达到GBT 4897．3-2003对在干燥状态下使用的家具及室内装修用板的性能要求。     

粉煤灰掺量对粉煤灰水泥竹碎料板生产中原料相适性的影响

水泥竹碎料板是利用水泥、粉煤灰和竹碎料为主要原料,辅之以其他添加剂,经一定加工工艺制成的一种无机刨花板.煤灰水泥竹碎料板是在水泥竹碎料板生产中以一定量的粉煤灰替代一定量的水泥制成的一种无机刨花板,它质量轻,强度高,耐久性、耐候性、耐火性、耐热性、隔音性好,可装饰性能强(板材具有很好的机械加工性能,可对其进行钻、锯、磨、钉、胶结等加工,板材表面可贴装饰纸、喷灰浆和油漆等),并具有较好的环保功能(以无机物水泥、粉煤灰作为胶凝剂,不存在游离甲醛和酚等污染,符合人们的健康要求),是一种优质的建筑装修材料,可广泛应用于室内外建筑装修等领域.     

在定型刨花板生产线上生产竹材刨花板的若干技术问题

竹材刨花板(亦称竹材碎料板)即按刨花板生产工艺生产出的性能与木质刨花板相近的人造板,它与近年来出现的竹材纤维板的主要区别在于前者刨花形态呈碎料状(片状、针状、颗粒状),后者呈纤维状。本文系从实际生产的角度,为刨花板生产厂家(特别是南方各省)提供一种新的刨花板生产原料来源及其技术。     

三种竹碎料板的物理力学性能比较分析

对三种竹碎料板的物理力学性能进行了比较分析。板材弹性模量：竹席增强竹碎料板〉竹碎料/木纤维复合板〉普通竹碎料板;静曲强度：竹席增强竹碎料板〉竹碎料/木纤维复合板〉普通竹碎料板;吸水率：普通竹碎料板〉竹碎料/木纤维复合板〉竹席增强竹碎料板;吸水厚度膨胀率：普通竹碎料板〉竹碎料/木纤维复合板〉竹席增强竹碎料板;内结合强度：竹碎料/木纤维复合板〉竹席增强竹碎料板〉普通竹碎料板。     

Testing of particle board by acoustic techniques

Summary The acoustic velocities of a wide range of particle boards were determined from measurements of the transit times of wave packets through the materials. Velocities measured along the plane of the board are dependent on the properties of the board's skin layer, and are reasonably well correlated with the board's modulus of elasticity (r=0.73) and modulus of rupture (r=0.65). Velocities measured perpendicular to the plane of the board are not so well correlated with the mechanical properties of the board — the most significant being the Z strength parameter (r=0.56). The results suggest that this form of non destructive testing would be more suited to production line monitoring than to replacing or complementing existing test methods.Present adress see p. 78     

Relation between the dynamic modulus of elasticity and the static modulus of elasticity,the modulus of rupture of mandarin peel–sawdust composite board

This study was conducted to determine the relation between the dynamic modulus of elasticity and the static modulus of elasticity, and the relation between the dynamic modulus of elasticity and the modulus of rupture of mandarin peel–sawdust composite boards. The result of this study was as follows: There was highly close linear correlation between the dynamic modulus of elasticity and the static modulus of elasticity, modulus of rupture of the mandarin peel–sawdust composite boards with the density of 0.4, 0.5 and 0.6 g/cm³, and the mandarin peel content of 10, 20, 30 and 40%, thus, the static modulus of elasticity and the modulus of rupture can be predicted from the dynamic modulus of elasticity measured by free vibration test using resonance frequency.     

Influence of growth stresses and material properties on distortion of sawn timber — numerical investigation

? The board distortion that occurs during the sawing and the drying process causes major problems in the utilisation of sawn timber. The distortion is highly influenced by parameters such as spiral grain angle, modulus of elasticity, shrinkage, growth stresses and sawing pattern.

? In this study a finite element simulation of log sawing and timber drying was performed to study how these parameters interact to affect board distortion. A total of 81 logs with different material combinations were simulated. From each simulated log four boards with different annual ring orientation were studied.

? The results showed that the elastic modulus, shrinkage coefficient and growth stresses had a large influence on the final bow and spring deformation. After sawing of the log into boards, the release of growth stresses was the main contributor to the bow and spring deformation. For boards with low modulus of elasticity, the bending distortion became larger than for the boards with high modulus of elasticity. The twist deformation was very small after sawing but increased significantly during drying of the boards. The results showed that spiral grain angle and the board location within the log were the main contributors to the twist deformation.

     

Properties of strand boards with uniform and conventional vertical density profiles

Randomly oriented strand boards with both uniform and conventional vertical density profiles (VDP) were manufactured, and their properties were evaluated and compared. The bending modulus of elasticity (MOE) of conventional strand boards was predicted using the laminated beam theory and the MOE-density regression equation from the uniform strand boards. The results showed that the predicted MOE of conventional strand boards was close to the measured MOE with a difference of less than 10%. The internal bond strength values of uniform strand boards were found to be higher than conventional strand boards while no significant difference was found in water-related properties. Compared with uniform strand boards, MOE values of conventional strand boards were improved only at higher density level. About 10% of improvement in MOE can be obtained for the strand boards investigated by manipulating the VDP. Steeper VDPs were predicted to be required for thinner boards than for thick boards in order to achieve the same improvement in MOE.     

杉木热处理材结晶度及力学性能的研究

热处理对木材力学性能的影响是多样的,这与热处理条件下木材的物理化学变化密切相关。本次研究将杉木板材在160℃、180℃和220℃常压蒸汽条件下进行热处理,考察处理材的结晶度、抗弯弹性模量、抗弯强度及相互可能的关联。结果表明,热处理使试材结晶度增加,有助于提高木材的刚性,使热处理材的抗弯弹性模量高于常规对照材;结晶度的提高对抗弯强度没有改善作用,热处理后试材的抗弯强度明显下降。     

利用微米木纤维定向重组技术形成超高强度纤维板的细胞裂解理论研究

采用人造板微观力学和木材细胞学理论，提出了一种利用定向重组微米木纤维技术形成超高强度人造板的细胞裂解理论和强度参数预测方法。应用提出的理论，可以根据纤维、木质素、细胞直径和排列的程度，建立理想状态下微米重组高强度定向纤维板木纤维细胞在定向重组微米技术形成超高强度人造板的细胞裂解理论，为人造板力学运用数学手段深入到细胞结构研究的深度提供了一种新的理论和方法。     

Manufacture and mechanical properties of binderless boards from kenaf core

Binderless boards were prepared from finely ground powders of kenaf (Hibiscus cannabinus L.) core under varying manufacturing conditions. This research was designed to investigate their mechanical properties and evaluate the various manufacturing conditions: pressing temperature and time, pressing pressure, board density, board thickness, grain size of raw materials, and addition of furfural. The mechanical properties (i.e., modulus of rupture and elasticity, internal bonding strength) of boards increased with increasing board density and met the requirement for 15 type medium-density fiberboard (MDF) by JIS A 5905-1994. Thickness swelling and water absorption of boards exceeded the maximum permitted levels for 15 type MDF and S20 grade hardboard by JIS A 5905-1994, which indicates the low water-resistant property of binderless boards. In contrast to that in usual wood-based materials, internal bonding strength showed significant correlations with other board properties: modulus of rupture and elasticity, thickness swelling, and water absorption. We confirmed experimentally that the best manufacturing conditions proved to be as follows: pressing temperature 180°C, time 10min; pressing pressure 5.3MPa; board thickness 5mm; board density 1.0g/cm³; average grain size 53µm; and powder with no furfural content.Part of this paper was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002     

Preparation and properties of waste tea leaves particleboard

Urea-formaldehyde (UF) adhesive is the main source of formaldehyde emission from UF-bonded boards. The components in waste tea leaves can react with formaldehyde to serve as a raw material in the production of low formaldehyde emission boards. In our study, waste tea leaves and UF adhesive were employed in the preparation of waste tea leaves particleboard (WTLB). An orthogonal experimental method was applied to investigate the effects of process parameters on formaldehyde emission and mechanical properties of WTLB. The results indicated that: 1) waste tea leaves had the ability to abate formaldehyde emission from boards; and 2) density of the WTLB was a significant factor affecting its modulus of rupture (MOR), modulus of elasticity (MOE) and internal bonding (IB).     

烟秆制备刨花板的力学性能研究

烟秆为烟草采摘烟口t-后的废弃物,为了更好的利用这种原料,利用不同含水率（9％、6％、3％、0％）和烟秆不同部位（上部、中部和下部）的刨花制成刨花板,测定刨花板的内结合强度、弹性模量和静曲强度,分析含水率和烟秆部位对刨花板力学性能的影响。结果表明,随着含水率从0增加至9％,刨花板的内结合强度从0．35MPa增加至0．58MPa,其弹性模量和静曲强度呈先增后减趋势,当含水率在6％时,烟秆刨花板的弹性模量和静曲强度最大。不同部位的烟秆刨花对刨花板的内结合强度、弹性模量、静曲强度有显著影响,其中,利用中部烟秆刨花制备的刨花板的内结合强度、弹性模量、静曲强度最小。利用烟秆刨花制备的刨花板其力学性能能达到国家标准的要求,因此利用烟秆制备刨花板是可行的。