Automotive Doors: New Technology and Trends

-------------------------------------------------------------------------------------------------------------------

----------

IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany

t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: [email protected] | w: www.iqpc.de

Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de

Automotive Doors – New Technology and Trends

Emissions from road transport increased by 26% between 1990 and 2008, with

passenger cars currently responsible for 12% of overall EU emissions of CO2 (1).

The EU introduced regulations for passenger cars in 2009 with targets for emission

levels that manufacturers must adhere to. By 2015 passenger cars should have

maximum emissions of 130g CO2/km, with a further target of 95g CO2/km to be

achieved by 2020. Limits for the emissions of light commercial vehicles were added

to the legislation in 2011, stating that the maximum should be no more than 175g

CO2/km by 2017 and 147g CO2/km by 2020.

These targets for reduced emissions are one of the biggest drivers of innovation in

the automotive manufacturing sector, with weight reduction at the forefront of

development. To meet the regulations each car manufacturer is assessed on the

emissions of their overall fleet. Every new car registered is given an indicative

emission level based on its mass, and manufacturers must ensure that the average

mass of all its cars is in line with the emission allowance. Heavier cars are targeted

for greater emissions than lighter cars, so the reduction in the mass of their overall

fleet will help manufacturers to comply with the legislation.

Trends

The automotive door sector is one area in which manufacturers are looking to

reduce overall weight by using alternative materials and new manufacturing

concepts. Door suppliers are continually striving to improve the design and

engineering of their products, and any reduction in weight will need to be integrated

with other areas of innovation such as noise reduction, closure and sealing systems

and keyless technology.

Brose

The automotive supplier Brose introduces a new concept in design last year when

they introduced a door system manufactured from wood-fibre reinforced

polypropylene (2). The door structure provides a 6% weight saving against

-------------------------------------------------------------------------------------------------------------------

----------




conventional door systems at no extra cost, and has several other advantageous

benefits. Wood-fibre reinforced plastic is a sustainable material which is carbon

neutral. The use of renewable and recyclable materials is another trend in the

industry, again in the pursuit of carbon emissions reduction.

Pictured below, the door system offers manufacturers protection from price

fluctuations in raw materials, such as plastics derived from crude oil. The carrier

plate is manufactured from polypropylene which has been reinforced with 40%

wood fibre. In comparison with a glass-fibre reinforced door system, the Brose

design reduces the amount of plastics used by 20%.

Source: Brose

Crash testing results showed that the door system offers the same level of safety as

a glass-fibre reinforced solution; and the integrated doors also contribute to better

thermal and acoustic insulation.

-------------------------------------------------------------------------------------------------------------------

----------




Magnesium Doors

The use of magnesium for car body parts, including doors, to replace steel could be

an option for manufacturers as it offers great potential for weight saving (3).

Magnesium parts can be manufactured which provide a similar rigidity to steel, but

are up to 50% lighter. Researchers at the Die Fraunhofer Institute for Machine Tools

and Forming Technology IWU designed and produced an example door last year

which was showcased at the Hanover Messe trade fair in April. The magnesium door

weighs just 4.7kg compared with a similar steel door at around 10.7kg.

The advantage of using magnesium is that it is a resource which is available in large

quantities world-wide, it can be easily moulded during production, and it possesses

much the same properties as steel. Engineers at the Fraunhofer Institute have

developed specific moulding technologies for wrought magnesium alloys, and it is

the processes they are developing which may lead to the use of magnesium in mass

production for car parts.

Tailored Blanks

The use of optimised sheet metal parts, manufactured specifically, is another

manufacturing option which can reduce weight and offers a variety of benefits for

car makers, such as reduced cost and enhanced crash protection. One company

supplying products to the automotive industry is ThyssenKrupp (4). They produce

tailored blanks constructed from individual sheets of steel of differing thickness,

strength and coating which are joined by laser welding. By tailor-making the

products, ThyssenKrupp ensure that the completed part has the right grade of steel

in the right place.

The tailored parts reduce the need for reinforcement and overlapping joints within

the part, so require less material which reduces weight. The targeted use of steel

with different properties also helps to lower cost as well as weight. The more

expensive materials are used only when necessary, while cheaper grades of steel

can be used in non-essential areas. The structural strength of the vehicle and the

crash performance can also be improved through the use of tailored blanks for

doors. The thicker, high strength steels are used in areas of high tension and areas

which may suffer the impact in a crash.

-------------------------------------------------------------------------------------------------------------------

----------




Mercedes-Benz F125!

Source: Daimler Technicity

One highly innovative design for a door system is the Mercedes-Benz F125! Concept

vehicle, pictured above. Engineers designed the car with a view to vehicles in two

generations time, and have developed several visionary features, not least the gull

wing doors. The research car has been built so that designers can study the future

for automobiles and obtain new knowledge about how different innovations work in

practice.

The doors are of a light weight and high strength CRP construction, while crash

protective systems built into the door allow the removal of the B pillar. The doors

allow access to all four seats of the vehicle at the same time, and can be controlled

from the front or rear seats of the car. Opening and closing of the doors is

completely contact-free from the outside, as simple wiping gestures can control all

of the functions, with a control element built into the rear side window. The doors

can be opened or closed from within the car by the simple touch of a button, while

outside, it is possible to use a smartphone to unlock and open the doors.

-------------------------------------------------------------------------------------------------------------------

----------




The F125! Is a design inspired by the thought of what the car may evolve into by

the year 2025, and gives an insight into one way in which the automotive door may

develop.

Fibre Reinforced Plastic

Fibre-reinforced plastics are becoming more and more commonplace in car

manufacturing as the trend towards weight reduction continues. Electric cars in

particular will benefit from the use of lighter materials due to the weight of the

heavy battery packs that they have to carry. Market research firm Lucintel (5),

revised its prediction for the growth of the carbon-fibre plastics market in its most

recent market report, “Growth Opportunities in the Carbon-Fibre Market 2010-

2015”. They estimated that the market could grow by 13% per year over the five

year period. Automotive manufacturing is sure to contribute to the growth in the

sector, and research is ongoing amongst manufacturers to develop more and more

parts and components from composite plastics.

Summary

The EU requirements for carbon emissions from passenger vehicles is pushing

manufacturers into developing newer and innovative technologies which can reduce

weight and contribute towards the targets. Door manufacturers have several other

demands from consumers which are also being developed alongside weight

reduction initiatives. Consumers and therefore car makers, demand more

technology in the door, as well as greater safety and security, and enhanced noise

reduction for greater comfort.

The challenge for door manufacturers is to integrate all of these requirements into

door systems which also save weight. The Brose development of a wood-fibre

polypropylene door system is one example of the types of door structures that could

soon be in serial production. The doors offer weight saving compared to steel door

systems, and provide extra thermal and acoustic insulation. The use of a

sustainable material such as wood-fibre has several advantages and is likely to be a

continuing trend in the coming years. Using renewable materials helps towards the

EU’s overall carbon emission targets, and lessens the reliance on fluctuating

material prices due to crude oil prices.

-------------------------------------------------------------------------------------------------------------------

----------




Magnesium doors are another trend which is likely to undergo rapid development in

the industry, as they offer substantial weight savings of up to 50% compared with

steel doors. Techniques being developed at the Fraunhofer Institute can produce

materials which have similar strength and rigidity to steel, and the processes they

are developing could see magnesium being put to use in mass production in the

automotive industry over the next few years.

The Mercedes-Benz F125! Research vehicle offers a glimpse into the future of auto

manufacturing, with a car designed with the 2025 and the evolvement of the

passenger car in mind. The gull wing concept completely removes the B pillar, and

the door is constructed from a light weight CRP material. Several technologies have

been integrated into the door with touch button controls and contact-free opening

from the outside via a smartphone.

Ultimately, manufacturers must develop designs in the future which can meet the

demand for lighter doors, with better crash protection, enhanced acoustic

performance, and integrated technology.

Colin Pawsey

Colin Pawsey’s background and experience is in the water heating industry, with a focus on

technical data analysis and energy efficient products for both commercial and residential

sectors. He also works as a freelance journalist focussing on renewable and sustainable

resources, energy efficiency, and consumer information.

-------------------------------------------------------------------------------------------------------------------

----------




References:

(1) http://ec.europa.eu/clima/policies/transport/vehicles/cars/faq_en.htm

(2) http://www.brose.de/ww/en/pub/press/content12499.htm

(3) http://www.fraunhofer.de/en/press/research-news/2011/april/resource-

friendly-car-manufacturing.html

(4) http://www.tailored-blanks.com/en/products/tailored-products/thyssenkrupp-

tailored-blanks.html

(5) http://www.lucintel.com/

Want to know more about automotive doors?

Check out our Download Centre, where you will find more articles,

white papers and interviews regarding this topic:

http://bit.ly/automotive-doors

http://ec.europa.eu/clima/policies/transport/vehicles/cars/faq_en.htm

http://www.brose.de/ww/en/pub/press/content12499.htm

http://www.fraunhofer.de/en/press/research-news/2011/april/resource-friendly-car-manufacturing.html

http://www.fraunhofer.de/en/press/research-news/2011/april/resource-friendly-car-manufacturing.html

http://www.tailored-blanks.com/en/products/tailored-products/thyssenkrupp-tailored-blanks.html

http://www.tailored-blanks.com/en/products/tailored-products/thyssenkrupp-tailored-blanks.html

http://www.lucintel.com/

Documents

Automotive Doors: New Technology and Trends