TEXTILES IN AUTOMOBILES

S.SIVAKUMARASSOCIATE PROFESSORDEPARTMENT OF AUTOMOBILE ENGINEERINGKUMARAGURU COLLEGE OF TECHNOLOGYCOIMBATORE-641049 9444283430

sivakumar.s.auto@kct.ac.in

Contents:

Mobiltech Fiber Composition in AutomobilesAutomobile Components using Textiles

Land – Air/Space – Water

• Upholstery, car interior, carpets• Tyres, car elements, filters,• Heat, cable & sound insulation,• Safety systems - airbags, seat belts• Protective covers for land crafts, boats, aircrafts• sailcloth, inflatable boats• Envelopes of balloons• Special equipment for military vehicles,

Mobiltech

Textiles in Automobiles

Visible components :

upholstery, carpets, headliners..(45 m2 approx.)

Concealed components :

tyre cords, hoses, belts, airbags, air and fuel filters, noise and vibration dampening and body panel reinforcement in composites etc.

Fiber composition in AutomobilesAPPLICATION AREAS

FIBRES / PRODUCTS USED

in %

UPHOLSTERY Polyester, wool, nylon, acrylic

18

TYRE CORDS & FABRICS

Polyester, Nylon, HT * rayon, steel & aramid

12.8

COMPOSITE Glass, carbon, aramid, HT polyester & polyethylene

14

RUBBER REIN-FORCEMENT

HT polyester, aramid

9.4

SEAT BELTS HT polyester 8.8

AIRBAGS Nylon - 6,6, nylon - 4,6

3.7

CARPETS Nylon, polyester, polypropylene

33.3

Source: David Rigby Associates

HT* High Tenacity

Tenacity = grams/denier (g/d)unit of measure for the linear mass density of fibers, is defined as the mass in grams per 9000 meters.

Seat Covers / Upholstery

Selection of fabric:Apart from strength & comfort,the fabric should also have

Resistance to Sun Light & UV Abrasion Resistance Reduced Flammability Odour free Antistatic Soil resistance.

Composition of seat coverIt is a trilaminate consisting of

o face fabric, o foam o scrim lining on the back.

The specifications of the laminate depend on where the laminate is used: seat central panel or back or door panel...

PET face fabric The foam is PE-PU or Polyether-PU; the latter

being more hydrolysis resistant & is suitable for humid climates

Foam density – 26 to 45 Kg/m3, 2 to 22 mm thick, fire resistant.

The scrim fabric is warp knitted (nylon or Polyester), 30-90 g/m2

Seat BeltsMultilayer woven narrow fabrics

– Maximum yarn packing for a given area to have maximum strength

– Twill or Satin– HT PET yarns (320 ends of 1100 dtex or 260 ends

1670 dtex)– Softer & flexible along the length for comfort– Rigidity along the width to enable it to slide

easily between buckles and retract smoothly into housings

– Scuff resistant but not unpleasantly hard edges

– Resistant to microorganisms

Performance Standards(Seat Belts)

Restrain a passenger weighing 90 Kg involved in a collision at 50 Km/h into a fixed object

Minimum straight pull strength 30kN/50mm Accelerated ageing Finished product – resistance to fastening &

unfastening 10,000 times

Air Bag

Squib, which is a small explosive device, ignites a propellant, sodium azide.

The azide burns with tremendous speed, generating nitrogen, which inflates the airbags.

Within 45 to 55 milliseconds the airbag is supposed to be fully inflated.

Within 75 to 80 milliseconds, the airbag is deflated and the event is over. 

The airbags are now designated as Supplemental Restraint System (SRS) or Supplemental Inflatable Restraints.

Fabrics for Airbag• The fabric from which the air bag is made must withstand the

force of the propellant chemicals. More importantly, the hot gases must not penetrate the fabric and burn the skin of the car occupant.

• The earlier airbags were Neoprene coated Nylon 6,6 but lighter and thinner silicon coated versions soon followed. Latter, uncoated fabrics have appeared.

• Airbags vary in size and configuration– driver side airbags: from 35 lit capacity upwards – for front passengers: form about 65 lit capacity upwards

Airbag(Fabric Quality Requirements)

• HT multi filament nylon 6,6 – 210, 420 and 840 denier• High tear strength, high anti seam slippage, controlled

air permeability (about 10L/m2/min) and be capable of being folded up into a confined space for over 10 years without deterioration.

• Some tests require 75% property retention after 4000 hrs at 90-1200C, the equivalent of 10 yrs. UV exposure and also cold cracking resistance down to -400C.

• Recently, Nylon 4,6 (Akzo) with melting point of 2850C has been introduced especially for airbags.

Recent Trends in Airbags

Side Air bags : as 30 % accidents occur due to side impact collisions

energy from front-impact collision is

absorbed by the bumper, hood and engine, takes 30 to 40 milliseconds before

it reaches the car's occupant.

in side impact

thin door and a few inches separate the occupant from another vehicle. This

means that door-mounted side airbags must begin deploying in a mere five or

six milliseconds!

Shaped AirbagsSide Airbag

There are essentially two types of side airbags commonly used today, the side torso airbag and the side curtain airbag.

Side airbag inflated Knee airbag It is located beneath the steering wheel. Knee airbags are designed to reduce leg injury.

Knee Airbag

Side Torso Airbag

Side-impact airbags or side torso airbags are a category of airbag usually located in the seat, and inflate between the seat occupant and the door. These airbags are designed to reduce the risk of injury to the pelvic and lower abdomen regions. Some vehicles are now being equipped with different types of designs, to help reduce injury and ejection from the vehicle in rollover crashes.

• Curtain airbags have been said to reduce brain injury or fatalities by up to 45% in a side impact with an SUV. These airbags come in various forms (e.g., tubular, curtain, door-mounted) depending on the needs of the application. Many recent have a long inflatable curtain airbag that protects all 3 rows of seats of high end vehicles.

Seat belt airbag

In 2009, the S-class ESF safety concept car showcased seatbelt airbags. They will be included standard on the production Lexus LFA in late 2010, and the 2011 Ford Explorer will offer rear seatbelt airbags as an option.

Rear curtain airbag

In 2008, the Toyota iQ launched featuring the first production rear curtain shield airbag to protect the rear occupants' heads in the event of a rear end impact.

Center airbag

In 2009, Toyota developed the first production rear-seat center airbag designed to reduce the severity of secondary injuries to rear passengers in a side collision.

On motorcycles

• Various types of airbags were tested on motorcycles by the UK Transport Research Laboratory in the mid 1970s.

• In 2006 Honda introduced the first production motorcycle airbag safety system on its Gold Wing motorcycle. Honda claims that sensors in the front forks can detect a severe frontal collision and decide when to deploy the airbag, absorbing some of the forward energy of the rider and reducing the velocity at which the rider may be thrown from the motorcycle.

• Airbag suits have also been developed for use by Motorcycle Grand Prix riders. They are connected to the motorcycle by a cable and deploy when the cable becomes detached from its mounting clip, inflating to protect the back.

Headliners• It is multilayer construction:

– Decorative face fabric– Soft touch PU foam– Chopped glass mat– Semi rigid PU foam (core material)– Chopped glass mat– Non-woven scrim fabric

All layers are hot pressed with thermo plastic powder/film

Nonwoven Applications• Bonnet: Bi-component yarn (nylon6 sheath with PET

cover) to reinforce acoustic insulation• Air-filters: nonwoven with activated carbon and

antibacterial chemicals to remove malodours• Carpets: less weight, low cost & recycling -

needle felt PP• Surfaces such as window seals, dash board

components – PET & Nylon 66 flocked surfaces to eliminate rattles & squeaks as well as contributing to overall aesthetics.

CARPETS• Carpets are classified according to their application and

location. TYPES APPLICATION LOCATION

Type 1 Door trim, quarter trim Inner side surface of 2-door car passenger compartment

Type 2 Trunk trim Rear trunk inside

Type 3 Floor Floor of passenger compartment

Type 4 Cargo floor, High floor High floor surface of vans

Type 5 Rear shelf Shelf behind rear seat

Tyres1. THE TYRE IS A COMPOSITE OF A RELATIVELY LOW

STRENGTH, HIGH ELONGATION RUBBER MATRIX & A HIGH STRENGTH, LOW ELONGATION TYRE CORD.

2. THE TYRE CORD GIVES THE TYRE SHAPE, SIZE, STABILITY, LOAD CARRYING CAPACITY, FATIGUE & BRUISE RESISTANCE.

3. TYRE CORDS ALSO AFFECT IMPACT RESISTANCE, RIDE, HANDLING, TREAD WEAR & FUEL ECONOMY

Composite market of India

Current level of composites production is 3,05,000 Metric Tonnes

The per capita usage of Composites in India is 0.24 kg which offers enormous potential for growth

Growth driving factors:Automotive and Marine sectors are changing from conventional steel/metal

combination to advanced composites.

Off-Shore wind energy will bring new innovation in advanced composites whereby a huge market will be made available.

Improvements made on the quality of raw materials, processes and on finished products has increased customer confidence.

Carbon FiberCarbon fiber is a long thin strand of carbon atoms that are bonded together in

a honeycomb crystal lattice called Graphene. Some of the Graphene layers are folded around each other in random

orientations but most are aligned parallel to the long axis of the strand. This makes the fiber incredibly strong along the axis of the strand. (highest

APF)  The strands are usually wound into a yarn then woven into a fabric. (By

altering the weave pattern the fabric can be stronger in one direction or be equally strong in all directions.)

The fabric is then mixed with epoxy and molded to form the desired shape.

A 6 μm diameter carbon filament compared to a human hair.

Fabric made of woven carbon filaments

Organic Polymers such as Polyacrylonitrile are spun or drawn into long thin strands.

Then the strands are heated to a temperature of 1,000-3,000° C for several minutes in a furnace filled with a gas mixture that does not contain oxygen.

The strands are twisted together into a yarn, which are then woven into a fabric.

The fabric is then impregnated with an epoxy to form a composite.

Stress-Strain Curve for Fabric

FUTURE

The factors influencing future of automotive textiles:

• Environment• Cost• Safety

THANK YOU