CCME, University of Newcastle upon Tyne Composites in Fire 3 9-10 September, 2003 WELCOME Introduction to basic ideas of composites in fire WELCOME Introduction.

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

WELCOMEWELCOME

Introduction to basic ideasIntroduction to basic ideas

of composites in fireof composites in fire

WELCOMEWELCOME

Introduction to basic ideasIntroduction to basic ideas

of composites in fireof composites in fire

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

FIRE REACTIONFIRE REACTION

The response of the material, especially in the early stages of a fire, and its interactions with the environment.

   Can be further subdivided into:

progress of the fire

human survivability.

   These can be regarded as characteristics of the material and can, quite often be determined from relatively small samples.

Many properties (for instance, time to ignition and surface spread of flame) are influenced by the material at the surface of the product.

The overall composition contributes to average heat release.

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

FIRE RESISTANCEFIRE RESISTANCE

the ability of the structure to retain functionality during a fire,

the ability of a physical barrier such as a wall, bulkhead or protective coating to limit heat flux and prevent damage to material remote from the fire

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

Properties and testsProperties and tests

Pool fire tests

Burner tests

Furnace tests

Jet-fire tests

FIRE RESISTANCE

Smoke generation

Toxicity indexHuman survivability

Oxygen index

Combustibility

Time-to-ignition

Surface spread of flame

Peak heat release

Average heat release

Single burning item test

Start-up and progress of fire

FIRE REACTION

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

Polymeric matrices are Polymeric matrices are flammableflammable

Fire requires:Fire requires: Fuel Oxygen Heat source

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

FuelFuel

Combustion occurs mainly in the Combustion occurs mainly in the gaseous phasegaseous phase

HeatHeat

OO22

SmokeSmoke

Combustion Combustion productsproductsFlameFlame

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

FuelFuel

Combustion requires:Combustion requires:

HeatHeat

OO22

SmokeSmoke

Combustion Combustion productsproducts

•gaseous fuelgaseous fuel•diffusiondiffusion

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

SolidSolidPolymerPolymer

VolatilesVolatiles++

CharChar

HeatHeat++

Combustion Combustion productsproducts

HeatHeat

OO22

Polymer combustion

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

SolidSolidPolymerPolymer

VolatilesVolatiles++

CharChar

HeatHeat++

Combustion Combustion productsproducts

HeatHeat

OO22

Polymer combustion

Effect of char Effect of char formation?formation?

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

CH2 CH2

CH2 CH2CH2

CH2 CH2

Phenolic resinPhenolic resin(or resin with high aromatic content)(or resin with high aromatic content)

Char Char

Char formation

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

SolidSolidPolymerPolymer

VolatilesVolatiles++

CharChar

HeatHeat++

Combustion Combustion productsproducts

HeatHeat

OO22

Polymer combustion

SuppressSuppresscombustion?combustion?

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

ADVANTAGE:ADVANTAGE: Considerable reduction in ignitability Considerable reduction in ignitability

and surface spread of flameand surface spread of flame

DISADVANTAGE:DISADVANTAGE: Only of real use when the Only of real use when the polymer itself is the main fuel source.polymer itself is the main fuel source.

When there is another fuel source, the polymer willWhen there is another fuel source, the polymer will

burn.burn.

Halogens produce increased smoke and toxicityHalogens produce increased smoke and toxicity

when the polymer does burn.when the polymer does burn.

NEVERTHELESS:NEVERTHELESS: Halogenated resins are still the Halogenated resins are still the mainstay of the industrymainstay of the industry

Halogenated systems

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

SolidSolidPolymerPolymer

VolatilesVolatiles++

CharChar

HeatHeat++

Combustion Combustion productsproducts

HeatHeat

OO22

Polymer combustion

Prevent heat Prevent heat from getting from getting to polymer?to polymer?

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

Thermal insulation (OK if its refractory, Thermal insulation (OK if its refractory,

i.e. rockwool, kaowool, Structogard etc.)i.e. rockwool, kaowool, Structogard etc.)

Thick laminate effectThick laminate effect

Surface intumescents (thick or thin films)Surface intumescents (thick or thin films)

Surface engineering - intumescent veils, layersSurface engineering - intumescent veils, layers

Internal intumescents Internal intumescents

ATHATH

Preventing heat from reaching polymer

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

Undamaged Undamaged

laminatelaminate

Laminate with Laminate with

decomposing decomposing

resinresin

VolatilesVolatiles

Behaviour of laminates: the thickness effect

In some circumstances the composite itself

can protect from fire

Composites in Fire 39-10 September, 2003

CCME, University of Newcastle upon Tyne

In conclusion, this brief introduction

summarises the various avenues

that are currently open to protect

composite structures from fire, and to

optimise their fire reaction properties.