A Study of the Flexural Properties of Jute Fabric Reinforced Epoxy Composite: Experimental and Uncertainty Analysis

ABSTRACT

The variability in natural fiber composite properties has always been problematic due to the dispersion in their mechanical properties resulting from fiber misalignment, irregular crosssection, fiber length, and geometry, which impacts their reliability. This issue of reliability has greatly affected the selection process of natural fiber composites as opposed to the synthetic fiber counterparts when it comes to strength, stiffness, failure strains, and energy absorption criteria. Stiffness is one property which greatly depends on the span length and load-bearing capacity of the material, which makes it an important criterion during product design. In this study, flexural properties of the jute fabric composite were studied through experiment and uncertainty analysis using various distribution functions. Jute epoxy composite at 38% fiber volume fraction was fabricated, and samples were machined using abrasive water jet machining as per ASTM D7264 standard for bend test. The samples were experimentally tested for bending strength, modulus, and failure strains, and uncertainty analysis was done to further analyze their failure behavior. Experimentally tested samples showed multimode bending failure such as M(CAT) and M(TAB) as per ASTM D7264.

摘要

天然纤维复合材料性能的可变性一直是个问题, 因为纤维错位, 不规则横截面, 纤维长度和几何形状等导致其机械性能分散, 从而影响其可靠性. 在强度, 刚度, 失效应变和能量吸收标准方面, 可靠性问题极大地影响了天然纤维复合材料的选择过程, 而不是合成纤维复合材料. 刚度是一个特性, 它在很大程度上取决于跨度和材料的承载能力, 这使得它成为产品设计中的一个重要标准. 本研究采用不同分布函数, 通过实验和不确定度分析, 研究了黄麻织物复合材料的弯曲性能. 制备了纤维体积分数为38%的黄麻-环氧复合材料, 并根据ASTM D7264弯曲试验标准, 使用磨料水射流加工 (AWJM) 加工样品. 对试样进行了弯曲强度, 模量和破坏应变的实验测试, 并进行了不确定度分析, 以进一步分析其破坏行为. 根据ASTM D7264, 经实验测试的样品显示出多模式弯曲失效, 如M(CAT) 和M(TAB) . 在使用平均值和标准偏差外推实验值后, 评估了弯曲性能的分散性, 其中弯曲强度和破坏应变分别遵循对数正态分布, 而弯曲模量则遵循威布尔分布. 这有助于理解复合材料的弯曲性能, 并预测不同荷载条件下的不同失效模式.

KEYWORDS:

• Jute fabric
• uncertainty analysis
• flexural properties
• stiffness
• distribution functions

关键词:

• 关键词
• 黄麻织物
• 不确定性分析
• 弯曲性能
• 刚度
• 分布函数

Highlights

• The mean values of the experimentally obtained bending strength, modulus, and failure strain were 70.92 MPa, 4.1204GPa, and 0.0178, respectively. Samples showed multimode bending failure of jute composite, which were reported after observing the fracture behavior, coded as M(CAT) and M(TAB) as per ASTM D7264.

• The variability of bending properties was studied using statistical models and found that the bending strength and failure strain followed lognormal distribution and the flexural modulus followed Weibull distributions.

• The lognormal distribution in bending strength indicates fewer imperfections with more samples and higher stiffness of the composite.

• The Weibull distribution in bending modulus indicates higher modulus values implying stiffer material and having higher energy absorbing capability.

• The high bending failure strain gave us an insight into the high interfacial bonding between matrix and reinforcement and also high load carrying capacity before the ultimate failure.

Acknowledgments

The authors would like to thank Dr. Atul R. Bhagat, Head of the composite lab at DRDL Imarat, Hyderabad, for his support in allowing them to perform the tests.

Disclosure statement

No potential conflict of interest was reported by the author(s).