ABSTRACT

The effects of fiber orientation and volume fraction on the mechanical and thermal properties of laminated jute reinforced polyester composite are investigated. The composite sheets of thickness 4.0 mm are fabricated by hand lay-up method using three laminated stacks of jute fibers and four different orientations (0°/90°/0°, 90°/0°/90°, 45°/0°/-45° and −45°/90°/45°). For each fiber orientation, two-volume fractions of 20% and 30% are used. The mechanical properties such as tensile, flexural, impact strength, modulus of toughness and elasticity, and hardness of the fabricated composites are evaluated by testing as per ASTM standard. The thermal conductivity of the composite sheets is determined by Lee’s method. It is found that the mechanical strength, surface hardness and thermal conductivity of the laminated jute reinforced polyester composite are increased with fiber volume fraction and varied with fiber orientation. The tensile strength, energy absorption and load-bearing capacity are found the highest for 45°/0°/-45°, second-highest for 0°/90°/0° and the lowest for −45°/90°/45° fiber orientation. The flexural strength is found the highest for 0°/90°/0° and the second-highest for 45°/0°/-45° fiber orientation. The method and procedure of this research work can be used to fabricating moderate size jute reinforced polyester composites with elevated in-plane strength in both longitudinal and lateral directions.

摘要

研究了纤维取向和体积分数对层压黄麻增强聚酯复合材料力学和热性能的影响。厚度为 4.0 mm 的复合板是通过手糊法制造的，使用三个层压堆叠的黄麻纤维和四种不同的方向（0°/90°/0°、90°/0°/90°、45°/0° /-45° 和 -45°/90°/45°）。对于每种纤维取向，使用 20% 和 30% 的两种体积分数。根据 ASTM 标准，通过测试评估制造的复合材料的机械性能，例如拉伸、弯曲、冲击强度、韧性和弹性模量以及硬度。复合片材的热导率由李氏法确定。发现机械强度，层压黄麻增强聚酯复合材料的表面硬度和导热系数随着纤维体积分数的增加而增加，并随着纤维取向的变化而变化。45°/0°/-45°的拉伸强度、吸能和承载能力最高，0°/90°/0°次之，-45°/90°/45°最低°纤维取向。弯曲强度在 0°/90°/0° 时最高，在 45°/0°/-45° 纤维取向时第二高。本研究工作的方法和程序可用于制造中等尺寸的黄麻增强聚酯复合材料，在纵向和横向上均具有较高的面内强度。0°/90°/0° 纤维取向第二高，-45°/90°/45° 纤维取向最低。弯曲强度在 0°/90°/0° 时最高，在 45°/0°/-45° 纤维取向时第二高。本研究工作的方法和程序可用于制造中等尺寸的黄麻增强聚酯复合材料，在纵向和横向上均具有较高的面内强度。0°/90°/0° 纤维取向第二高，-45°/90°/45° 纤维取向最低。弯曲强度在 0°/90°/0° 时最高，在 45°/0°/-45° 纤维取向时第二高。本研究工作的方法和程序可用于制造中等尺寸的黄麻增强聚酯复合材料，在纵向和横向上均具有较高的面内强度。