Fluids and Mechanical Materials

Learning Outcomes

Subject Specific Intellectual and Research Skills

Having successfully completed this module you will be able to:

• Calculate the extent of diffusion-driven composition changes and to predict the equilibrium microstructure of a material from the phase diagram
• Design composite materials to meet particular mechanical requirements
• Understand the terminology of thermodynamics and be able to communicate with other engineers. Know the different forms of energy and understand what is meant by work and heat
• Outline the fundamental behaviour of fluids
• Recommend methods for prevention of metallic corrosion
• Specify an appropriate heat treatment to improve alloy’s mechanical properties given the phase diagram for that alloy
• Relate the microstructure and composition of materials to their mechanical properties and B8. Select materials for different applications based on the constraints of the given applications

Knowledge and Understanding

Having successfully completed this module, you will be able to demonstrate knowledge and understanding of:

• The mechanical behaviour of fluids, polymers, viscoelastic materials, semicrystalline polymers, crystalline structures and composites
• Techniques used to determine the structure and mechanical properties of materials
• Make general predictions about the ability of the given material to resist failure
• The underlying principles governing Fluid Mechanics and Thermodynamics
• The molecular characteristics of polymers and the application of thermodynamic principles to explain aspects of the behaviour of polymers
• Solve common fluid mechanics design problems, including examples of conservation of mass, momentum and energy analysis
• Understand the laws of thermodynamics, the Energy Equation and the importance of entropy
• Failure mechanisms of modern engineering materials: metal alloys, polymers, ceramics, composites

Subject Specific Practical Skills

Having successfully completed this module you will be able to:

• Identify the appropriate model for fluid mechanical problems and determine a solution
• Interpret micrographs in relation to mechanical properties
• Explain the failure mechanism for given sample

Transferable and Generic Skills

Having successfully completed this module you will be able to:

• Solve mathematically based problems for engineering applications
• Use fundamental knowledge to identify pertinent information for analysis
• Solve numerical problems
• Demonstrate study and time management skills
• Study and learn independently

Introduction Fluids and Other Materials: - Properties: density, pressure, temperature, viscosity, surface -tension/capillary action - Definitions: Newtonian fluids, non-Newtonian fluids, plastics Hydrostatics: - Hydrostatic pressure and head, absolute/gauge and atmospheric pressure, the hydrostatic paradox, measurement by manometer - Forces on free surfaces - Buoyancy and submerged and floating body stability Fluid mechanics: - Compressible and incompressible flow - Laminar and turbulent flow, Reynold’s number, mean velocity - Continuity of flow (conservation of mass). - Conservation of momentum - Applications: force on plates from jets, pipes and curved pipes from jets, jet reaction - Force/propulsion - Streamlines, Euler’s equation, Bernoulli’s equation, and Navier-stokes - Applications: Closed conduit flow/ pipe flow, Reynolds number, friction loss, Moody diagram Thermodynamics 1 - Introduction and thermodynamic terminology, systems (open and closed), properties, processes, cycles, work, heat, specific heat, temperature (zeroth law of thermodynamics), internal energy, enthalpy. - First Law of Thermodynamics First law and SFEE; specific heats of gases, application to non-flow processes Fluid mechanics and Thermodynamics: - Applications of SFEE to nozzles, diffusers, turbines - Conservation of energy and applications to fluid flow, pitot tube, ecryst meter Thermodynamics 2: - Second Law of Thermodynamics Statement of the law, heat engines, cycle efficiency, reversible and irreversible cycles and processes, the Carnot cycle, the reversed Carnot cycle, concept of entropy. Molecular Structure of Polymers: - Polymerisation - Molecular architecture - Copolymerisation - Thermoplastics and thermosets Amorphous Polymers: - Brittle materials - The glass transition - The thermodynamics of deformation - The entropy spring - Viscoelasticity, creep, stress relaxation and superposition - Representations of elastic and viscous behaviour - The Kelvin Model of viscoelasticity - The Maxwell Model of viscoelasticity Ordering in Polymers: - The thermodynamics of crystallisation - Fractionation, segregation and properties - Environmental stress cracking and crazing - Synthetic and biological fibres - Fibre compactions Blends and Composites: - The thermodynamics of mixing - The mechanical properties of miscible and immiscible blends - Copolymerisation – structure and mechanical properties - Anisotropy in aligned long-fibre composites - Short fibre composites – end effects, and orientation Properties of engineering materials relevant to failure: - Engineering stress-strain curves - Yield strength and hardness - Brittle and ductile materials; impact and fracture toughness - Fatigue and creep resistance - Corrosion Elements of fracture mechanics: - Criteria for brittle and ductile fracture, relation between yield strength and toughness, Ductile- Brittle Transition Temperature - Designing of tough materials, metal-matrix composites Metals and Alloys: microstructure vs mechanical properties - Crystalline and polycrystalline solids, grains and grain boundaries - Dislocations motion as a primary plastic deformation mechanism - Grain size, solution, order, precipitation and dispersion strengthening - Energy stored in grain boundaries and dislocations, effect of Cold Work - Microstructure control in metal alloys during solidification - Free energy as a driving force, phase diagram, partition coefficient - Annealing: recovery, ecrystallization and grain growth - Precipitation, nucleation and growth, dispersion strengthened alloys Diffusion: - Thermal activation - Steady-state and transient processes - Surface hardening via diffusion

Summative

This is how we’ll formally assess what you have learned in this module.

Referral

This is how we’ll assess you if you don’t meet the criteria to pass this module.

Repeat

An internal repeat is where you take all of your modules again, including any you passed. An external repeat is where you only re-take the modules you failed.