Related Experiment Video
Updated: Mar 22, 2026
08:36
Fragility Assessment of Bovine Cortical Bone Using Scratch Tests
Published on: November 30, 2017
10.1K
The fracture toughness of eggshell
David Taylor1, Megan Walsh1, Alexandra Cullen1
1Trinity Centre for Bioengineering, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland.
Acta Biomaterialia
|April 26, 2016
Summary
We measured the fracture toughness (Kc) of hen eggshells, finding a value of 0.3MPa√m. This low value, lower than previously reported, explains why eggshells are brittle and break easily due to defects.
Area of Science:
- Materials Science
- Biomechanics
- Engineering
Background:
- Avian eggshells are known for their brittleness, a critical factor in protecting developing embryos.
- Understanding the mechanical properties of eggshells is essential for both biological and industrial applications.
- Previous measurements of eggshell fracture toughness (Kc) have been inconsistent and potentially inaccurate.
Purpose of the Study:
- To accurately measure the fracture toughness (Kc) of commercial hen eggshells using a novel method.
- To investigate the reasons behind the exceptionally low fracture toughness of eggshells compared to other calcium carbonate materials.
- To analyze the impact of various defects on eggshell strength and understand defect tolerance.
Main Methods:
- Development and application of a novel method for measuring fracture toughness (Kc).
- Application of the Theory of Critical Distances and Weibull probability theory for defect analysis.
- Comparative analysis of eggshell mechanical properties with other natural materials.
Main Results:
- A novel fracture toughness (Kc) value of 0.3MPa√m was obtained for hen eggshells, significantly lower than previously reported.
- The low toughness is attributed to the prevention of natural toughening mechanisms.
- Analysis revealed how cracks, holes, and notches affect the strength of whole eggs.
Conclusions:
- The unique mechanical properties of eggshell (low Kc, high Young's modulus) are optimized for protecting the developing chick while allowing hatching.
- The study provides accurate data on eggshell fracture toughness and defect tolerance, crucial for the egg industry.
- The findings challenge previous assumptions and offer a clearer understanding of eggshell mechanics.
More Related Videos
Related Concept Videos
01:22Toughness and Hardness of Aggregate
792
Toughness and hardness are critical properties of aggregate materials used in concrete, particularly on pavement surfaces and industrial flooring subjected to heavy loads. Toughness is defined as the aggregate's resistance to failure by impact and is measured by the aggregate impact value (AIV). For this, the aggregate impact value test is performed, wherein the impact is delivered by a standard hammer, which falls freely under its own weight onto the aggregates. The aggregates fragment in...
792
01:24Stress-Strain Diagram - Brittle Materials
4.9K
Brittle materials, including glass, cast iron, and stone, exhibit unique characteristics. They fracture without considerable change in their elongation rate, indicating that their breaking and ultimate strength are equivalent. Such materials also show lower strain levels at the point of rupture. The failure in brittle materials predominantly results from normal stresses, as evidenced by the rupture created along a surface perpendicular to the applied load. These materials do not display...
4.9K
01:18Mechanical Characteristics of Steel
1.2K
The mechanical characteristics of steel are assessed through various tests that evaluate its strength, toughness, and flexibility. These tests include tension, torsion, impact, bending, and hardness assessments, each providing crucial information about steel's suitability for specific applications.
The tension test is fundamental for determining tensile strength. In this test, a steel specimen is stretched using a gripping device until it breaks. The data collected during this test are used...
The tension test is fundamental for determining tensile strength. In this test, a steel specimen is stretched using a gripping device until it breaks. The data collected during this test are used...
1.2K
01:27Fractures: Bone Repair
6.4K
Treatment for a fracture is based on the type of break, the bone affected, and the patient's age.
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the...
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the...
6.4K
01:15Brick Durability, Strength, and Appearance
781
Brick durability, strength, and appearance are crucial factors in construction, influencing the choice of bricks for specific applications. The process of freeze-thaw, for instance, significantly affects brick durability. This phenomenon occurs when water absorbed by a brick expands as it freezes, potentially causing damage when it melts and refreezes. Bricks are graded for durability: SW-grade bricks are the most durable, offering high strength and low water absorption, followed by MW-grade...
781
01:21Impact Strength of Concrete
693
Impact strength in concrete is a critical measure that reflects the material's capability to endure the forces applied during pile driving and when supporting machinery foundations that experience impulsive loads. It is also essential when handling precast concrete components to prevent accidental damage. The impact strength is assessed by observing the concrete's resistance to repeated impacts and energy absorption capacity. A key indicator of significant damage to concrete is when it...
693