Overview Research area Most recent projects highlights Dr. Elaheh Ghassemieh Mechanical Engineering Department University of Sheffield
Research areas Nonwovens Novel materials and their processes Bio-composites Nano-composites Natural based fibre composites Biodegradable polymers Ceramics Titanium alloys Nano tubes Nano clay In elastomers Hemp, flax, palm fibre In thermoplasticthermoset Scaffold, dental implants, membranes Packaging High pressure and temperature seals Wear resistant rubber Biomaterials, automotive, packaging, oil& petroleum industry Body panels Automotive Transport Packaging
Research Areas (continued) Hydroentanglement Optimised/novel manufacturing processes Ultrasonic consolidation Optimised drilling process Ultrasonic welding 3 dimensional hybrid metal structures Adaptive metal structures Titanium /CFC stack Aluminium /CFC stack Thermoplastic and NF composites Aerospace, Automotive
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 Most recent projects 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 1. 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
Research team PhD students Mr. Rahul Cadambi Mr. Ozden Isbilir Mr. Davood Rouholamin Mr. Graham Gagg Mr. Teddy Mbwadzawo Ms. Hoda Amel Mr. Farhan Raza Mr. Marton Huszar Ms. Shirin Sharhbaf Mr. Cheeseng Tan
Nanocomposite of elastomers for enhanced life (high pressure- temperature) Optimizing the processing of nanocomposites Enhance the resistance to explosive decompression Increase the life and performance of the elastomer 12 C15A 72h Ball Milled 1 As Received C15A Volume, % 8 6 4 C15A 48h Ball Milled 2 C15A 96h Ball Milled.1.1 1 1 1 Particle Diameter, µm XRD Graphs for CLOISITE 15A Relative Intensity 25 2 15 1 C15A As Recd C15A Freeze Dried C15A 3 mins Sonication C15A 96h Ball Milling 5 3 4 5 6 7 8 9 1 11 12 Angle 2θ 35 3 tensile @ room temp tensile @ 1 C elongation @ room temp elongation @ 1 C 35 3 25 25 Tensile Strength, MPa 2 15 2 15 Elongation at break, % 1 1 5 5 HNBR Std HNBR C15A FD HNBR C2FD HNBR KC
Optimisation of the geometry of the drill bit and process parameters for cutting hybrid composite/metal structures in new aircrafts Improving the life of the tool and reducing the wear on drill Preserving the quality of the holes produced, reduced delamination and burr formation 35 3 CFC first run second run 25 Force ( N ) 2 15 1 5 1 5 9 13
Embedding Active/Passive elements in Adaptive Structures using Ultrasonic consolidation 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 P applied Path, parallel to the direction of vibration V f S onotrod e 2 mm 2 mm t s Foil t f Substrate 1 mm w 25 2 15 1 Stress (MPa) 5-1.6-1.2 -.8 -.4.4.8 1.2 1.6-5 -1-15 -2 Strain -25 (%) Friction work (m J/m m 2 ) 14 12 1 8 6 4 2 8.4 1.4 12.4 Amplitude of ultrasonic vibration (μm) 21 19 17 15 13 11 9 Fracture Energy (J/m 2 )
Bio-Degradable 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. 35 3 25 PLA / HA scaffolds 45. μ 4. m 35. Degree of Anisotropy Wall Thickness 1.6 1.4 1.2 Freq uency (% ) 2 15 1 Top face Bottom face 3. 25. 2. 15. 1..8.6 5 1..4-1 1-2 2-3 3-4 4-5 5-6 6-7 Equivalent pore diameter (Microns) 5.. Pure PLA PLA/1%HA PLA/3%HA PLA/5%HA.2. Stress ( MPa) 1 9 8 7 6 5 4 3 2 Stage 1 1 Stage 2 HA/TCP Neat PLA HA and PLA Stage 3 1 2 3 4 5 6 7 8 9 Strain (%) Modulus (MPa) 2. 18. 16. 14. 12. 1. 8. 6. 4. 2.. Gibson Model (85%) Our test (85%) Gibson Model (9%) Our test (9%) 1 3 5 PLA & (%HA)
Design, manufacture and characterization of patient specific porous 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 for reduced carbon footprint in automotive/sustainable development applications 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 health/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-1 Silica (Half Size) 9 85 8 Phase Angle 75 7 65 3% 4% 5% 5.5% 6% 6.25% 6.5% 6 55 5.1 1 1 1 Frequency (Hz) 18 o Peel 18 16 14 Force (N) 12 1 8 6 4 2 1mm/s 1mm/s 1mm/s Speed Veet Boots Nair
Evaluation of the Design & Performance of Loading & Unloading Systems using Ambulance 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 force (N) compression force (kn) compression force (kn) 3 15-15 loadi ng unload ing Measured Calculated Failure Limit -3-3 -15 time (s) 15 3 5 4 3 2 1 8 6 4 2 AW1 ramp AW2 ramp failure limit -15-1 -5 5 1 15 time (s) easi-loader AW1 tail-lift AW2 tail-lift AW1 ramp AW2 ramp failure limit -35-25 -15-5 5 15 25 35 time (s) Failure Criteria L4/L5 Disc : 3.4kN
The influence of the interface lute on the structural integrity of full coverage machined ceramic restorations 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 fullcoverage machined ceramic crown. Standard crown preparation Cemented machined ceramic crown Ceramic crown Resin cement Tooth Pulp Tooth