The key difference between delamination and spalling is that delamination occurs by crack extension along a plane parallel to the surface, whereas spalling occurs as a subsequent propagation of the crack through the film.
Delamination and spalling are terms related to particle physics. Delamination can be defined as areas having poor or no bonding between adjacent layers. Spalling is the formation of fragments of a material that is broken off a larger solid body. These are two types of crack extensions. Typically, a crack extension tends to proceed by brittle rupture mechanisms.
CONTENTS
1. Overview and Key Difference
2. What is Delamination
3. What is Spalling
4. Delamination vs Spalling in Tabular Form
5. Summary – Delamination vs Spalling
What is Delamination?
Delamination can be defined as areas having poor or no bonding between adjacent layers. This occurs as the most crucial damage for impacted composite. It takes place from the layers in the composite laminate. Moreover, delamination is a result of matrix cracking, bending cracks, and shear cracks. It can affect the compression strength of composite laminate and can slowly cause the composite to experience failure through buckling. The stress that is experienced by the composite initiates cracks and causes delamination between these laminates, leading to more severe damage.
Typically, upon low or high velocity impact events, several damage modes can occur when a composite laminate experiences impact. This can include matrix crack, delamination, fiber crack, and fiber pullout. Moreover, these damage modes are dependent on the impact parameter, such as impact energy and impactor mass or impactor shape.
What is Spalling?
Spalling is the formation of fragments of a material that is broken off a larger solid body. A spall can form from a variety of mechanisms: as a result of projectile impact, corrosion, weathering, cavitation, and excessive rolling pressure. Therefore, the terms spalling and spallation both refer to the process of surface failure where the spall is shed.
Spalling is a term adopted from the term spall, which comes from particle physics. For example, it is used on neutron scattering instruments. Mechanical spalling can take place when there are high-stress contact points such as ball bearings. Moreover, it can occur according to brinelling in which the maximal sear stress takes place, not at the surface but just below where the shearing the spall off.
Moreover, spalling can take place as a result of cavitation. Cavitation is where fluids are subjected to localized low-pressure conditions that can cause vapor bubbles to form. Generally, this can happen in pumps, water turbines, vessel propellers, and piping under some conditions.
What is the Difference Between Delamination and Spalling?
Delamination and spalling are terms related to particle physics. Delamination refers to areas having poor or no bonding between adjacent layers, whereas spalling refers to the formation of fragments of a material that is broken off a larger solid body. The key difference between delamination and spalling is that delamination occurs by crack extension along a plane parallel to the surface, whereas spalling occurs as a subsequent propagation of the crack through the film. In addition, delamination occurs at the film/substrate interface, while spalling occurs via propagation of the crack through the film.
The following table summarizes the difference between delamination and spalling.
Summary – Delamination vs Spalling
Delamination and spalling are terms related to particle physics. These refer to two types of crack extensions. The key difference between delamination and spalling is that delamination occurs by crack extension along a plane parallel to the surface, whereas spalling occurs as a subsequent propagation of the crack through the film.
Reference:
1. “Delamination.” An Overview | ScienceDirect Topics.
2. “Spalling.” Wikipedia. Wikipedia Foundation.
Image Courtesy:
1. “GVFKA Stone Tool Craftsman Show Spalls” By DanielPenfield – Own work (CC BY-SA 4.0) via Commons Wikimedia