Corrosion Inhibition at Scribed Locations in Coated AA2024-T3 by Cerium- and DMTD-Loaded Natural Silica Microparticles under Continuous Immersion and Wet/Dry Cyclic Exposure

Earlier studies on cerium-loaded naturally occurring silica microparticles (i.e., diatomaceous earth) demonstrated the potential to efficiently protect small scratches in epoxy-coated AA2024-T3 panels during relatively short immersion times. The current work investigates the potential of such inhibitor-loaded microparticles to protect wide...

Finite element modelling of creep cavity filling by solute diffusion

In recently discovered self healing creep steels, open-volume creep cavities are filled by the precipitation of supersaturated solute. These creep cavities form on the grain boundaries oriented perpendicular to the applied stress. The presence of a free surface triggers a flux of solute from the matrix, over the grain boundaries towards the...

Damage evolution in a self-healing air plasma sprayed thermal barrier coating containing self-shielding MoSi ₂ particles

A self‐healing thermal barrier coating (TBC) system is manufactured by air plasma spraying (APS) and tested by thermal cycling. The ceramic topcoat in the self‐healing APS TBC system consists of an yttria stabilised zirconia (YSZ) matrix and contains self‐shielding aluminium containing MoSi2 healing particles dispersed close to the topcoat/bond...

Autonomous high-temperature healing of surface cracks in Al₂O₃ containing Ti₂AlC particles

In this work, the oxidation-induced crack healing of Al₂O₃ containing 20 vol.% of Ti₂AlC MAX phase inclusions as healing particles was studied. The oxidation kinetics of the Ti₂AlC particles having an average diameter of about 10 μm was studied via thermogravimetry and/or differential thermal...

A review study on encapsulation-based self-healing for cementitious materials

Encapsulation-based self-healing technology is an effective method for healing the crack-deteriorated cementitious material. Encapsulation-based self-healing initiates by crack occurrence and progresses by chemical reaction of released self-healing agents in the cracks, which are contained in capsules. In this paper, a review has been...

Development of a fracture fatigue test for lifetime quantification of footwear outsoles: a preliminary application to self-healing polymers

Previous research showed fracture failure in the outsole of sports footwear. There was no method available for the quantification of the material behavior in with this failure mechanism. Therefor the goal of this research was to develop a mechanical test method for quantification of fatigue fracture behavior of a material when a crack is present...

Kinetics of self-healing reaction in TBC with MoSi2 based sacrificial particles

An investigation into the relaxation response of a self-healing dual network polymer through controlled introduction of strain damage

Self-healing ability in polymers is typically probed by monitoring restorative properties after localized macroscopic damage or repetitive cycles of destructive testing followed by a healing cycle (e.g. cut-and-heal tests). However, the restoration of homogeneously distributed damage before ultimate failure remains largely unattended in...

Coating of MoSi2 healing particles for self-healing thermal barrier coatings

To increase lifetime of the protective thermal barrier coatings (TBC) in jet engines and other gas turbines, a self-healing approach based on MoSi2 healing particle addition is considered. However, due to rapid oxygen transport in yttria-stabilized zirconia (YSZ), a common TBC material, premature oxidation is a major problem. This thesis...

Additive manufacturing of a self-healing thermoplastic polyurethane

Additive manufacturing of smart polymers is a rapidly growing field. Additive manufacturing presents a versatile, low-waste manufacturing method for functional materials. Self-healing polymers are a type of smart polymers that are able to mend damage, either by the incorporation of an encapsulated healing agent or by intrinsic polymer design....

On the in situ encapsulation of MoSi2B healing particles in YSZ TBCs: Self-healing of thermal barrier coatings (TBCs)

A novel method to encapsulate MoSi2B healing particles was explored via in situ shell formation in yttria-stabilised zirconia thermal barrier coatings (YSZ-BCs). The shell formation was analysed for MoSi2B healing particles alloyed with 2, 6 and 12 wt% Al. According to oxidation kinetics study at 1100˚C using thermogravimetry, MoSi2B-12 wt% Al...

Mechanical testing and quantification of crack healing in self-healing yttria-stabilized zirconia thermal barrier coating

Thermal barrier coatings (TBC) are often applied to hot components of modern turbojet engines. These coatings increase the performance of the engine and enhance the lifetime of its structural components. Thus, improving the TBC lifetime is related with a reduction of maintenance costs and increased reliability. As an alternative to conventional...

Modelling self-healing magnetic textures in hydrodynamic bearings

Hydrodynamic bearings can be used to minimise friction, and their load capacity can be improved by texturing the bearing surfaces. However, due to mechanical contact between the surfaces during start and stop, these textures are susceptible to wear. Previously, a new method of creating textures using magnetorheological fluids as lubricant was...

On the use of Laser Speckle Imaging to study local polymer dynamics

Synthesis and oxidation behaviour of Ta-Al-C MAX phases

MAX-phase materials, a class of ternary carbides and nitrides that combine favorable properties of metals (conductivity and toughness) and ceramics (high temperature strength) have been shown to autonomously heal micro-cracks by high temperature oxidation. The investigation of Ta and Al containing MAX phases (Ta2AlC & Ta4AlC3) could render self...

Recent Advances in Magnetic Polymer Composites for BioMEMS: A Review

The objective of this review is to investigate the potential of functionalized magnetic polymer composites for use in electromagnetic micro-electro-mechanical systems (MEMS) for biomedical applications. The properties that make magnetic polymer composites particularly interesting for application in the biomedical field are their biocompatibility...

Self-Healing Asphalt Review: From Idea to Practice

In recent decades, researchers have revealed the great healing potential of asphalt and proposed various novel methods to inspire and improve the self-healing capacity of asphalt aimed to prolong the service life of asphalt pavement. In this review, up to date research progresses in induction healing and embedded rejuvenator encapsulation are...

Effect of diisocyanate mixtures on the healing of thermoplastic polyurethanes

Self-healing materials and, in particular, polymers are characterized by their ability to partially or fully restore their original properties or functions after damage. Amongst the healable polymer classes, thermoplastic polyurethanes have received increasing attention in the last years. This is mainly due to their broad application areas, the...