Short answer

When designing with hybrid composites, be aware that increasing glass fiber content will compromise viscoelastic properties like creep resistance and stress relaxation, impacting long-term structural integrity under bending.

Field: Final Production
Source: Procedia Structural Integrity (2020)
Method: Experimental testing
Evidence: Moderate effect

Incorporating glass fibers into carbon fiber composites, particularly at higher proportions, leads to a noticeable decrease in bending properties and an increase in creep displacement, indicating a less resilient viscoelastic response. This final production research insight is drawn from a 2020 study published in Procedia Structural Integrity. Using Experimental testing, researchers explored how this design variable affects real-world outcomes. The key design takeaway: When designing with hybrid composites, be aware that increasing glass fiber content will compromise viscoelastic properties like creep resistance and stress relaxation, impacting long-term structural integrity under bending.

Study

Final ProductionHigh ImpactModerate effect

Hybrid Composites Exhibit Reduced Viscoelastic Performance with Increased Glass Fiber Content

Procedia Structural Integrity · 2020

Key Findings

01Higher glass fiber content in hybrid composites leads to decreased bending properties.
02Increased strain rates result in higher maximum bending stresses and bending modulus.
03Hybrid composites with glass fibers exhibit greater stress relaxation and creep displacement compared to full carbon fiber composites.
04The stress relaxation and creep displacement increase proportionally with the glass fiber content.

Application

Design takeaway

How to apply

When specifying materials for structural components subjected to bending, analyze the expected strain rates and duration of loading. Use this data to select a composite layup that balances cost, weight, and the required viscoelastic performance, potentially favoring carbon fibers for critical applications.

Project actions

01When selecting materials for a design project, research how different fiber types affect the material's properties under various stress conditions.
02Consider the environmental factors and expected usage scenarios that might influence material performance over time.

Method & Evidence

AimTo investigate the influence of hybridizing glass and carbon fibers on the viscoelastic properties of composite materials under bending loads.

MethodExperimental testing

ProcedureExperimental tests were conducted in bending mode using composite laminates with varying ratios of glass and carbon fibers. The performance of hybrid composites was compared to laminates made solely of glass or carbon fibers. Measurements included stress relaxation and creep behavior over a 180-minute period at different strain rates.

ContextMaterials science and engineering, specifically composite material development.

Variables

IVFiber type (glass vs. carbon) and fiber content ratio.

DVBending properties, stress relaxation, creep displacement.

CVStrain rate, test duration, bending mode.

Strengths & Limitations

Strengths

+Direct experimental comparison of hybrid composites against monolithic ones.
+Investigation of both creep and stress relaxation phenomena.

Limitations

The experiments only looked at bending and for a short period (180 minutes). Real-world use might involve different types of forces or much longer durations.

Reliability & validity

The study's validity is supported by direct experimental comparison and the examination of key viscoelastic parameters. Reliability would depend on the reproducibility of the composite manufacturing process and the precision of the testing equipment.

Think critically

How might the observed viscoelastic behavior of hybrid composites influence the design of products intended for dynamic environments or those requiring precise dimensional stability over extended periods?

Design Principles

"The viscoelastic performance of composite materials is directly influenced by the constituent fiber types and their proportions, with carbon fibers generally offering superior resistance to creep and stress relaxation compared to glass fibers."

Understanding the viscoelastic behavior of hybrid composites is crucial for predicting their long-term performance and durability under various loading conditions. This insight informs material selection and design strategies for applications where components are subjected to sustained loads or dynamic stresses.

What This Means for Your Design

Adding more glass fibers to a composite made with carbon fibers makes it bend more and deform over time when you push on it, especially if you push it fast.

How to use in your project

1.Reference this study when discussing the material selection process for your design project, particularly if you are considering hybrid composites and need to justify your choice based on performance characteristics.

Add to My Project

Quick Cite

Paragraph starter

The selection of composite materials for this design project was informed by research into their viscoelastic properties. Studies such as Santos et al. (2020) indicate that hybrid composites, while offering potential benefits, exhibit reduced viscoelastic performance with increased glass fiber content. Specifically, higher proportions of glass fibers lead to greater creep and stress relaxation under bending loads, suggesting that for applications requiring long-term stability under sustained stress, a higher carbon fiber content or alternative material may be more suitable.

Source

Procedia Structural Integrity

The hybridisation effect on the viscoelastic properties of polymeric composites

journal · 2020

View source

Questions About This Research

What does the research say about hybrid composites exhibit reduced viscoelastic performance with increased glass fiber content?: When designing with hybrid composites, be aware that increasing glass fiber content will compromise viscoelastic properties like creep resistance and stress relaxation, impacting long-term structural integrity under bending. Evidence: Procedia Structural Integrity (2020).
Why does "Hybrid Composites Exhibit Reduced Viscoelastic Performance with Increased Glass Fiber Content" matter for design?: Understanding the viscoelastic behavior of hybrid composites is crucial for predicting their long-term performance and durability under various loading conditions. This insight informs material selection and design strategies for applications where components are subjected to sustained loads or dynamic stresses.
How can designers apply this research?: When designing with hybrid composites, be aware that increasing glass fiber content will compromise viscoelastic properties like creep resistance and stress relaxation, impacting long-term structural integrity under bending.
What were the main findings?: Higher glass fiber content in hybrid composites leads to decreased bending properties.. Increased strain rates result in higher maximum bending stresses and bending modulus.. Hybrid composites with glass fibers exhibit greater stress relaxation and creep displacement compared to full carbon fiber composites.. The stress relaxation and creep displacement increase proportionally with the glass fiber content.
What research method was used?: Experimental testing.
How strong is the evidence?: Evidence strength is rated Moderate effect, based on a 2020 journal from Procedia Structural Integrity.
What should I do differently in my next project?: When specifying materials for structural components subjected to bending, analyze the expected strain rates and duration of loading. Use this data to select a composite layup that balances cost, weight, and the required viscoelastic performance, potentially favoring carbon fibers for critical applications.
What are the limitations?: The study focused specifically on bending modes and did not explore other loading conditions. The long-term effects beyond 180 minutes were not investigated.