Influence of recycled carbon fiber addition on the microstructure and creep response of extruded AZ91 magnesium alloy

In this study,the recycled short carbon fiber(CF)-reinforced magnesium matrix composites were fabricated using a combination of stir casting and hot extrusion.The objective was to investigate the impact of CF content(2.5 and 5.0 wt.%)and fiber length(100 and 500μm)on the microstructure,mechanical properties,and creep behavior of AZ91 alloy matrix.The microstructural analysis revealed that the CFs aligned in the extrusion direction resulted in grain and intermetallic refinement within the alloy.In comparison to the unreinforced AZ91 alloy,the composites with 2.5 wt.%CF exhibited an increase in hardness by 16-20%and yield strength by 5-15%,depending on the fiber length,while experiencing a reduction in ductility.When the reinforcement content was increased from 2.5 to 5.0 wt.%,strength values exhibited fluctuations and decline,accompanied by decreased ductility.These divergent outcomes were discussed in relation to fiber length,clustering tendency due to higher reinforcement content,and the presence of interfacial products with micro-cracks at the CF-matrix interface.Tensile creep tests indicated that CFs did not enhance the creep resistance of extruded AZ91 alloy,suggesting that grain boundary sliding is likely the dominant deformation mechanism during creep.

Save plastic trash disaster:recycling fiber faces shuffle of the industry

In recent years,with the concept of green development and the basic national policy of conserving resources and protecting the environment,China speeds up the construction of a resource-saving and environment-friendly society,and forms a new pattern of harmonious development of man and nature.In many tasks of textile industry,it's undoubtedly a

In-Situ Growing of Branched CNFs on Reusable RCFs to Construct Hierarchical Cross-Linked Composite for Enhanced Microwave Absorption

The recycling of carbon fibers and protection from unwanted microwave radiation are two important environmental issues that need to be addressed in modern society.Herein,branched carbon nanofibers(CNFs)were grown in-situ on recycled carbon fibers(RCFs)through the chemical vapor deposition method using nickel as catalysts and thiophene as aided-catalysts.The effect of thiophene on the growth morphology of CNFs was investigated.Correspondingly,branched CNFs-RCFs and straight CNFs-RCFs were respectively obtained in the presence and absence of thiophene.The microstructure and electromagnetic behaviour investigations have shown that the branched CNFs possess a typical multi-branched structure,with more defects,pores and a larger specific surface area than the straight CNFs,which lead to better impedance matching and adequate dielectric loss ability for the branched CNFs-RCFs.The reflection loss(RL)results show that the branched CNFs-RCFs exhibit an optimum RL of -23.6 dB at 1.5 mm and a best effective absorption bandwidth(EAB)of 7.5 GHz at 2.0 mm.This research provides an innovative microwave absorbing material with adequate absorbing strength and outstanding EAB,while also promoting the sustainable reuse of the RCFs resources.

Manufacturing and Product Analysis of Non-Woven and Paper Based Epoxy Composites

Fiber-reinforced polymer composites are used in a wide variety of applications due to their many advantages, such as relatively low production costs, ease of fabrication, and superior strength compared to pure polymer resins. Polymer reinforcement can be either synthetic or natural. Synthetic fibers such as carbon have high specific strength, but their application fields are limited due to their high manufacturing cost. Recently, interest in recycled fiber-based composites has increased due to their many advantages. In this context, research has been carried out to better utilize non-woven and paper-based materials to make value-added products. The aim of the current research work is to compare the mechanical performance of non-woven and paper-based reinforced epoxy composites manufactured by the VARTM process. Mechanical properties such as tensile strength, flexural strength (using three-point bending), impact strength, hardness strength, and water absorption were measured. A multi-criteria decision approach called TOPSIS (The Technique for Order of Preference by Similarity to Ideal Solution) was used to select the best alternative from the investigated materials.