Elastic and Strength Properties of Continuous/Chopped Glass Fiber Hybrid Sheet Molding Compounds

Abstract A major technical challenge for modern aero engines is the development of designs which reduce noise and emission whilst increasing aerodynamic efficiency and ensuring aeroelastic stability of low-temperature engine components such as fans and low-pressure compressors. Composites are used in aviation due to their excellent stiffness and strength properties, which also enable additional flexibility in the design process. The weight reduction of the turbomachine components, due to composite materials and lighter engines, is especially relevant for the design and developments of hybrid-electric or distributed propulsion systems [1]. To accomplish this, a representative volume element (RVE) of a glass-fiber reinforced polymer is created, describing the geometrical arrangement of the textile reinforcement structure within the polymer matrix. For both phases, realistic linear elastic properties are assumed. This RVE will be investigated with the finite element method under various loading conditions to assess its anisotropic elastic properties and also its damping behaviour for elastic waves. To study the influence of delamination on the mechanical properties, small defects will be introduced into the model at the interface between reinforcement and matrix. Based on this micromechanical approach, a constitutive model for the composite will be formulated that describes the anisotropic properties as well as the damping behaviour. This constitutive model is then used to describe the material response in a macro-mechanical model, which serves as the basis for an aeroelastic analysis of a 1/3-scaled high-speed fan using a conventional (Ti-6Al-4V) and fiber composite material.

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Use of Rice Husk Powder as a Substitute for CaCO3 in Thermoset-Based Molding Compounds

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2007.1982 ◽

2007 ◽

Vol 1 (1) ◽

pp. 87-93 ◽

Cited By ~ 1

Author(s):

Chuleeporn Thanomsilp ◽

Silvano Cauchi-Savona ◽

Ton Peijs ◽

Saran Posyachinda

Keyword(s):

Mechanical Properties ◽

Calcium Carbonate ◽

Glass Fiber ◽

Rice Husk ◽

Filler Particle ◽

Volume Ratio ◽

Charpy Impact ◽

Molding Compounds ◽

Uniform Dispersion ◽

Cold Pressed

This paper explores the potential of using rice husk powder (RHP) as a substitute or in combination with calcium carbonate (CaCO3) fillers for its application in glass fiber/polyester molding compounds. In each case, one type of filler particle was used, while three formulations of filler combinations were selected: 100% RHP, 50:50% RHP:CaCO3, and 100% CaCO3. The constituents were kept at a constant volume ratio of resin:fibers:filler at 63:12:25% in all the formulations investigated. A sigma-bladed mixer was used to mix the compounds to a uniform dispersion. These were subsequently cold-pressed, post-cured, and tested for flexure, tension, and notched-Charpy impact. The results showed that the strength of the composites increases with increasing RHP, while the stiffness decreases when the CaCO3 is replaced by RHP. However, weight-for-weight, the composites containing RHP exhibit better or at least comparable mechanical properties to those containing solely CaCO3.

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