OverviewOverview

Research area Research area Most recent projects highlightsMost recent projects highlights

Dr. Elaheh Ghassemieh

Mechanical Engineering Department

University of Sheffield

Research areasResearch areas

Novel materials and their processes

Bio-composites

Biodegradable polymers

Ceramics

Titanium alloys

Scaffold, dental implants, membranes

Packaging

Natural based fibre composites

Hemp, flax, palm fibre In thermoplastic-thermoset

Body panels Automotive –Transport

Packaging

Biomaterials, automotive, packaging, oil& petroleum industry

Nano-composites

Nano tubes

Nano clay

In elastomers

High pressure and temperature seals

Wear resistant rubber

Nonwovens

Optimised/novel manufacturing processesOptimised/novel manufacturing processes

Aerospace, Automotive

Ultrasonic consolidation

3 dimensional hybrid metal structures

Adaptive metal structures

Ultrasonic welding

Thermoplastic and NF composites

Titanium /CFC stack

Aluminium /CFC stack

Optimised drilling process

Hydroentanglement

Research Areas (continued)

1. Nanocomposite of elastomers for enhanced life in Harsh Environment

2. Optimisation of the geometry of the drill bit and process parameters for cutting hybrid composite/metal structures in new aircrafts

3. Bio-Degradable Sintered Composites of PLA and HA in Scaffolds

4. Ultrasonic welding of the composites

5. Green/recyclable composites for reduced carbon footprint in automotive/sustainable development applications

6. Design, manufacture and characterization of patient specific porous titanium based implant

7. Embedding Active/Passive elements in Adaptive Structures using Ultrasonic consolidation

8. Developing pressure sensitive adhesive with better efficacy in health/personal care applications

9. Large Strain Behaviour of Syntactic Foam Damping Material

10. The influence of the interface lute on the integrity of machined ceramic restorations

11. Novel hybrid nano-elastomers designed for longer fatigue life and improved energy absorbing properties

12. Coating of elastomers for reduced permeability and high wear resistance

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Research team

PhD students

Mr. Rahul CadambiMr. Ozden Isbilir

Mr. Davood RouholaminMr. Graham Gagg

Mr. Teddy MbwadzawoMs. Hoda AmelMr. Farhan Raza

Mr. Marton HuszarMs. Shirin SharhbafMr. Cheeseng Tan

Nanocomposite of elastomers for enhanced life (high pressureNanocomposite of elastomers for enhanced life (high pressure--temperature)temperature)

•Optimizing the processing of nanocomposites•Enhance the resistance to explosive decompression•Increase the life and performance of the elastomer

XRD Graphs for CLOISITE 15A

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elongation @ 100°C

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• Improving the life of the tool and reducing the wear on drill• Preserving the quality of the holes produced, reduced

delamination and burr formation

Optimisation of the geometry of the drill bit and process parameOptimisation of the geometry of the drill bit and process parameters for ters for cutting hybrid composite/metal structures in new aircraftscutting hybrid composite/metal structures in new aircrafts

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• Optimisation of the process parameters for best quality weld and embedding• Understanding the mechanism of the process using FE simulation • Quantifying the effect of the process parameters on the two dominant effect

during process

Embedding Active/Passive elements in Adaptive Structures using Embedding Active/Passive elements in Adaptive Structures using Ultrasonic consolidationUltrasonic consolidation

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BioBio--Degradable Sintered Composites of PLA and HA in ScaffoldsDegradable Sintered Composites of PLA and HA in Scaffolds

• Processing of biodegradable composite scaffolds of PLA and HA through sintering and porogen leaching.

• Evaluation of the suitability of the manufactured composite for scaffold applications.

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Design, manufacture and characterization of patient specific Design, manufacture and characterization of patient specific porous titanium based implantporous titanium based implant

•Design of the patient specific implant •Manufacturing of the prototype implant using Laser sintering or 3D printing•Characterisation of the implant

Optimisation of the processing of green/recyclable composites foOptimisation of the processing of green/recyclable composites for r reduced carbon footprint in automotive/sustainable development reduced carbon footprint in automotive/sustainable development

applicationsapplications

•Improving adhesion of the fibre and resin using chemical treatments• Manufacturing the natural fibre composite using vacuum moulding or RTM (optimising)• Evaluation of moisture absorption, specific strength an stiffness and impact properties, failure and fatigue.

Developing pressure sensitive adhesive with better efficacy in Developing pressure sensitive adhesive with better efficacy in health/personal care applicationshealth/personal care applications

• New formulations for improving the efficacy of the cold wax strip • Establishing the in vitro tests to replace the most variable and expensive in vivo tests • Identification of the human factors and methods of measuring the variables and their

effects• Establishing the quality check tests on the lab products and new formulations

C-10 Silica (Half Size)

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Evaluation of the Design & Performance of Loading & Unloading SyEvaluation of the Design & Performance of Loading & Unloading Systems using stems using Ambulance StretchersAmbulance Stretchers

• Analysis of the loading & unloading of Ambulance Stretchers• Comparison of the Stretcher Systems (Tail-lift, Ramp-winch and easi-loader)• Evaluation of the Risk of Injury for the Ambulance Workers during the process

of loading and unloading

Failure CriteriaL4/L5 Disc : 3.4kN

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The influence of the interface lute on the structural integrity The influence of the interface lute on the structural integrity of of

full coverage machined ceramic restorationsfull coverage machined ceramic restorations

Resin cement

Cemented machined ceramic crown

Tooth

Standard crown preparation

Ceramic crown

Tooth

Pulp

• the effect of the interface dimensions and the elastic modulus of the lute on the structural integrity of a tooth restored with an adhesively retained full-coverage machined ceramic crown.