Hamed Yazdani Nezhad

• Doctor of Philosophy in Mechanical Engineering
• Professor (Associate) at University of Leeds

This study explores the impact of pre-existing silicon and carbon vacancies on the microwave heating of 3C-SiC at an atomistic level using molecular dynamics simulations. Microwaves were introduced at different electric field strengths (0.1 and 0.5 V/Å) and different frequencies (100, 150, 200, 250 and 300 GHz) to the vacancy-induced 3C-SiC crystal...

Magnetically actuated cilia are currently under research, due to their potential applications within microfluidics, soft robotics or even versatile manipulation and sensing. Additionally, they have an advantage over other actuation methods, as they require a simpler set-up, easier fabrication, and control. This report investigates the impact of ch...

This project aims to conduct research on the hyperelastic deformation of cilia-like structures under cruise flow conditions. Research was undertaken to obtain geometric features for cilia-like micropillars. The analysis done was for individual cilia-like structures to further study the mechanical deformation. A computational approach was taken to m...

This chapter conducts a thorough exploration of integrating “two-dimensional (2D) materials” with “silicon (Si) complementary metal oxide semiconductor (Si-CMOS)” devices, with a focus on applications in electronics, photonics, and energy. Various integration strategies are discussed, encompassing the synthesis and characterization of “2D materials...

Volumetric additive manufacturing (AM) of composites is an emerging manufacturing area of research and development with the potential to revolutionise all parts manufacturing. However, one of the primary hurdles is achieving a time/cost-effective AM process capable of precise control over material properties and reinforcement distribution in comple...

Electric field-induced strain is one of the most well-known characteristics of ferroelectric materials and it has been widely used for electromechanical applications. When an electric field is applied to a ferroelectric material with a perovskite structure, there are mainly three representative deformation behaviours that contribute to its mechanic...

In the current research, the response of magnetostrictive composites to external magnetic fields has been investigated. The composite, comprised of magnetic particles embedded in polymers, is distinguished by its ability to undergo dimensional, elastic, and electromagnetic changes in the presence of a magnetic field. Contrasting with bulk magnetost...

The current paper reports on the quantification of the effect of magnetic fields on the mechanical performance of ferromagnetic nanocomposites in situ during basic standard tensile testing. The research investigates altering the basic mechanical properties (modulus and strength) via the application of a contact-less magnetic field as a primary atte...

Electric field-induced strain is one of the most well-known characteristics of ferroelectric materials which has widely been used for electromechanical applications. The intrinsic strain emerges from the electrostriction and piezoelectric effects of the materials while the extrinsic strain is mainly attributed to the domain wall movement in the pol...

Hybrid nanocomposites integrating nanostructured zinc oxide (ZnO) and carbon quantum dots (CQDs) with designed heterostructures possess exceptional optical and electronic properties. These properties hold immense potential for advancements across diverse scientific and technological fields. This review article investigates the synthesis, properties...

Synthetic polymers have shown a great impact on every aspect of our life and attained an exponential rise in their production and utilization in the past decades due to their durability, flexibility, moldability, and inexpensive nature. However, the use of natural polymers or development of safe and environment-friendly synthetic bio-based polymers...

Few layers Black phosphorus (BP) and phosphorene are two-dimensional (2D) materials renowned for their adjustable bandgaps, high carrier mobility, and anisotropic conductivity, which make them highly promising for applications in the visible and infrared spectrum. The incorporation of these materials into polymer matrices has led to significant adv...

MXenes, a rapidly growing family of two-dimensional (2D) transition metal carbides, nitrides, or carbonitrides (Mn+1XnTx, where M is a transition metal, X is carbon, nitrogen, or both, and T represents surface functional groups), have captured the scientific community's interest due to their exceptional physicochemical properties and diverse techno...

A novel approach to tailoring strain energy in polymer composite is presented. The current article reports on the research conducted for the quantification and the state of reversibility of the mechanical strains induced by microwave field in solidified, dielectric enhanced polymers, to interconnect strain energy and field polarisation for reversib...

Two-dimensional (2D) materials have attracted considerable research interest due to their precisely definedproperties and versatile applications. In this realm, borophene - a single atomic sheet of boron atoms arranged ina honeycomb lattice - has emerged as a promising candidate. While borophenes were theoretically predicted tohave unique structura...

This review navigates the intricate landscape of Carbon Quantum Dots (CQDs) and polymer nanocomposites, illuminating their synthesis, distinctive properties, and multifaceted applications. Delving into diverse synthesis techniques, including hydrothermal, microwave-assisted, and pyrolysis methods, the study underscores the nuanced optimization nece...

The micro-light emitting diode (µLED) technology is poised to revolutionise display applications through the introduction of nanomaterials and Group III-nitride nanostructures. This review charts state-of-the-art in this important area of micro-LEDs by highlighting their key roles, progress and concerns. The review encompasses details from various...

Nanocomposite materials, particularly those reinforced with graphene nanoplatelets (GNPs) and Barium Titanate (BaTiO3), have been the focus of extensive study within diverse industries aiming to enhance mechanical and electrical properties. This thesis investigates the intricate relationship between external mechanical and electrical stimuli and th...

This feasibility study focused on the development of a CDPM technique for polymer composite manufacturing. It has aimed to demonstrate that hypothetically there is a strong correlation between dielectric data and the cure state (e.g. degree of cure) at a specific location in the material, as it interprets the polymerisation state in real-time. Ther...

The current article reports on the research conducted for the quantification and the state of reversibility of the mechanical strains induced by microwave field in dielectric enhanced polymers. This would suggest a remote strain energy tailoring technology in polymer composites. The electromagnetic field excitation of functionalised ferroelec...

The incorporation of design engineering into the already well-established area of materials engineering and materials mechanics to advance the field of soft robotics with particular reference to biomedical engineering and medicine. Established laws and concepts of magnetism were developed with those regarding mechanical deformation in order to nume...

Uncertainty quantification (UQ) and propagation (UP) in complex multi-scale physical models are challenging problems due to the high-dimensionality of the inputs and the outputs for such models and the corresponding computational complexity. These challenges could be tackled using Gaussian process (GP) models by constructing a surrogate response su...

This project delved into the extrusion process of standalone and nanocomposite filaments, focusing on PLA and PLA with iron for 3D printing applications. A comprehensive literature review was conducted to gain a thorough understanding of the extrusion process, material properties, and 3D printing techniques. A modified Felfil extruder was employed...

The research investigates optimal mechanical performance via the manipulation of process parameters found in laser equipped automated fibre placement (LAFP). The presented study was conducted in partnership with Novotech Aerospace Advanced Technology Srl. The mechanical performance of Polyetheretherketone (PEEK) and Polyetherimide (PEI) reinforced...

This project aims to primarily investigate the process of fabricating bio-inspired metamaterial geometries for use in developing an artificial, life-size phantom brain model. The following report documents on the challenges associated with the process of designing and manufacturing carbon composite structures, aiming to investigate the limitations...

This report investigates the development of deformable polymer structures, precisely by bending, by externally applied magnetic fields rather than electric fields. Specifically, the purpose is to manipulate internal strain energy remotely. The research focused on the different geometries and materials used in various studies and compared them to se...

A novel, zero‐waste and recycling plastic waste solution is introduced, to scalably produce graphene nanoplatelets/barium titanate (GNP/BaTiO3) polymer nanocomposite fibrils. A comprehensive investigation is performed to evaluate the compatible and non‐compatible recycled polypropylene (PP)/polyethyleneterephthalate (PET) blends combined with funct...

The concept of soft robots has garnered significant attention in recent studies due to their unique capability to interact effectively with the surrounding environment. However, as the number of innovative soft pneumatic actuators (SPAs) continues to rise, integrating traditional sensors becomes challenging due to the complex and unrestricted movem...

A Numerical Analysis of the relationship between Magnetic Fields and the deformation of Magnetic Structures

The development of efficient, energy-saving, and automated manufacturing of free-form variable-thickness polymer composite components has created a step-change and enabled technology for the composites industry seeking geometry tailoring during a mould-less and/or additive manufacturing such as that in 3D printing. The current article presents rese...

Epoxy is widely used material, but epoxy has limitations in terms of brittleness in failure, and thus researchers explore toughening and strengthening options such as adding a second phase or using electromagnetic fields to tailor toughness and strength, on demand and nearly instantaneously. Such approach falls into the category of active toughenin...

Silicon carbide (SiC) is widely used as a susceptor for microwave hybrid heating applications owing to its exceptional microwave absorbing characteristics. In practice, it is challenging to characterize the thermo-physical behaviour of the microwave irradiated SiC-based targets experimentally due to interference of integrated measurement devices wi...

Composites Assembly for High Performance Fastener-less Structures provides a broad and balanced span of information, covering both fundamentals and applications across academic and industrial state-of-the-art research and development on assembly, joining, inspection and repair of high-performance structures made from fibre-reinforced polymer compos...

Over the last years of research on drug delivery systems (DDSs), natural polymer-based hydrogels have shown many scientific advances due to their intrinsic properties and a wide variety of potential applications. While drug efficacy and cytotoxicity play a key role, adopting a proper DDS is crucial to preserve the drug along the route of administra...

Epoxy is an important class of thermosetting material which have been used in many fields such as aerospace, automobile, and energy sectors. Cured epoxy, however, exhibits poor resistance to crack initiation and growth, thus exhibiting low toughness and brittleness at failure. To improve the mechanical properties, epoxy matrix in polymer composites...

This article reports research on the development and implementation of new methods for structurally integrated and recyclable polymer based electronic products via multi-head fused deposition modelling (FDM) 3D printing. The focus of this research is to propose an efficient FDM-3D printing process utilising multiple filaments with no interruption o...

This paper investigates the optimal design for a repairing composite patch with adhesive bonding approach. The effects of the patch parameters were investigated individually, and the FEA was generated using Abaqus in order to measure the maximum stress. The results concluded that the parameters of the patch have different effect in terms of stress...

The present investigation focuses on developing cost-effective Carbon/Glass/Kevlar fiber-reinforced polymer hybrid composite laminates for achieving its synergistic effect on flexural and impact performance. It investigates the effect of stacking sequence induced by the use of different fiber types (Kevlar = K, glass = G, and carbon = C) on the fle...

Epoxy is an important class of thermosetting material which have been used in many fields such as aerospace, automobile and energy sectors. cured epoxy, however, exhibits poor resistance to crack initiation and growth, thus low toughness and brittleness at failure. To improve the mechanical properties, in numerous studies the epoxy matrix in polyme...

This work demonstrates an experiment process that led to the results, which show the possibility of materials which contain ferromagnetic nanoparticles to deform during the sample manufacturing under the presence of the magnetic field. The results indicate that further research and development of technology for such manufacturing will enable broade...

Composite materials are largely applicated in the aerospace industry because of their light weight and physical properties which can be easily shaped. Thus, slowly stringers transitioned from metallic materials to composites. The project, in partnership with Novotech Aerospace Advanced Technology S.r.l, aims at design and development of curved comp...

This report concerns a project, in partnership with Novotech s.r.l, that involved a detailed study into the behaviour of semi-crystalline and amorphous thermoplastic composite materials undergoing Laser-assisted Automated Fibre Placement (AFP) process. Polyether-imide (PEI) and Poly-ether-etherketone (PEEK) were studied as the reference case in thi...

A feasibility study has been performed systematically to develop a real-time contactless measurement of the dielectric properties (DP) of composite surface by means of a high-frequency, free-space vector network analyser (VNA) associated with one steel conical horn antenna (mono-static method). Examinations of the dielectric spectra of thermoset ep...

Matrix toughening is one of the most popular approaches to improve the overall fracture toughness of polymer composite materials. The most widely known approach for matrix toughening is the addition of a second phase such as rigid or/and rubber particles to dissipate the fracture energy, and vessels that containing healing agents that prevent furth...

Failure in an epoxy polymer composite material is prone to initiate by the coalescence of microcracks in its polymer matrix. As such, matrix toughening via addition of a second phase as rigid or/and rubber nano/micro-particles is one of the most popular approaches to improve the fracture toughness across multiple scales in a polymer composite, whic...

This paper investigates and discusses the outcomes from an ongoing feasibility research being conducted at Advanced Composites Research Focused Group on 3D printing polymers and carbon composites subjected to localised magnetic field force lines. Magnetic equipped composite processes are starting to become an important new development for structura...

This review aims to consolidate scattered literature on thermally sprayed coatings with nonionizing electromagnetic (EM) wave absorption and shielding over specific wavelengths potentially useful in diverse applications (e.g., microwave to millimeter wave, solar selective, photocatalytic, interference shielding, thermal barrier‐heat/emissivity). Ma...

In recent years, the number of small satellite launches has increased significantly due to technological advancement allowing space to be more accessible and to be commercialised. As of the end 2020, market research shows that the number of small satellite launches has reached a record number high bringing it up to a total of 1163 small satellites...

A Neural Network algorithm was designed to predict the interlaminar stresses in a multi-layered composite panel given the ply orientation and the in-plane stresses. To extract the interlaminar stresses, a time-intensive shell-cohesive analysis was conducted using FEA Software (ABAQUS), which consisted of introducing thin cohesive layers between the...

MXenes are a quickly growing and extended group of two-dimensional (2D) substances that have earned unbelievable analysis credits for various application areas within different manufacturing areas. Due to novel essential architectural and physicochemical properties shows good properties, such as elevated exterior area, living adaptability, strong e...

Graphene based materials e.g., graphene oxide (GO), reduced graphene oxide (RGO) and graphene nano platelets (GNP) as well as Barium titanate (BaTiO3) are emerging reinforcing agents which upon mixing with epoxy provides composite materials with superior mechanical, electrical and thermal properties as well as shielding against electromagnetic (EM)...

Failure in an epoxy polymer composite material is prone to initiate by the coalescence of microcracks in its polymer matrix. As such, matrix toughening via addition of a second phase as rigid or/and rubber nano/micro-particles is one of the most popular approaches to improve the fracture toughness across multiple scales in a polymer composite, whic...

Weight reduction and improved strength are two common engineering goals in the joining sector to benefit transport, aerospace, nuclear industries among others. Here, in this paper, we show that the suitable addition of carbon nanomaterials to a tin-based solder material matrix (C-Solder® supplied by Cametics Ltd.) results in two-fold strength of so...

This paper investigates and discusses the outcomes from an ongoing feasibility research being conducted at Advanced Composites Research Focused Group on 3D printing polymers and carbon composites subjected to localised magnetic field force lines. Magnetic equipped composite processes are starting to become an important new development for structura...