Session 5 - Body / Closures
Chair: Dr. Dietrich Wieser
Director Business Development Ground Transportation, Alcoa Europe, Bonn, Germany
Session 4 consists of five presentations dealing with various aspects of body and closures. The session presentations run from 13:30 until 16:00 o'clock.
13:30-14:00 High Strength Aluminum Sheet For Automotive Applications
Dr. Dirk Uffelmann
AMAG rolling GmbH, Ranshofen, Austria
Abstract
The most common aluminum alloys for automotive sheet applications are work hardening 5000-series alloys and heat-treatable 6000-series alloys. The are used in a wide range of chassis applications, components, structural parts and hang-onparts. From a general view, the use of these alloys results in a reasonable ratio of cost per weight saving and a good compatibility with existing production techniques in terms of forming and joining. Superior yield strength and tensile strength can be achieved by heat-treatable 2000- and 7000- series alloys, commonly used for aircraft applications. For certain automotive applications, there is additional weight saving potential by use of these high-strength aluminum alloys. The purpose of this paper is to show the possibilities and limitations of weight saving by use of high-strength aluminum alloys with respect to production (forming, joining, heat treatment) and vehicle performance (corrosion, fatigue, crash performance).
The most common aluminum alloys for automotive sheet applications are work hardening 5000-series alloys and heat-treatable 6000-series alloys. The are used in a wide range of chassis applications, components, structural parts and hang-onparts. From a general view, the use of these alloys results in a reasonable ratio of cost per weight saving and a good compatibility with existing production techniques in terms of forming and joining. Superior yield strength and tensile strength can be achieved by heat-treatable 2000- and 7000- series alloys, commonly used for aircraft applications. For certain automotive applications, there is additional weight saving potential by use of these high-strength aluminum alloys. The purpose of this paper is to show the possibilities and limitations of weight saving by use of high-strength aluminum alloys with respect to production (forming, joining, heat treatment) and vehicle performance (corrosion, fatigue, crash performance).
14:00-14:30 On the use of cladded aluminium sheets for different automotive appications
Dr. Henk-Jan BrinkmanResearch & Development Center, Hydro Aluminium Deutschland GmbH, Bonn, Germany
Abstract
Innovations in cladded aluminium products enable new aluminium sheet solutions for automotive applications, and give the possibility to improve the property mix of existing aluminium sheet solutions. This paper will deal with developments based on cladded non heat treatable AlMg aluminium alloys. Examples are novel cladded products intended for tank applications that show an improved performance with regard to the demands on strength, corrosion resistance and visual appearance. A further example is the use of cladded sheet products for applications were, next to other requirements, both strength and corrosion resistance are required. Also, developments in heat treatable AlMgSi body sheet alloys will be presented which show that in some cases a monolithic solution is available with a property mix that is competitive with were today a cladded solution is sometimes preferred. An example is a door inner applications were there is a simultaneous demand for high formability and good corrosion properties.
Innovations in cladded aluminium products enable new aluminium sheet solutions for automotive applications, and give the possibility to improve the property mix of existing aluminium sheet solutions. This paper will deal with developments based on cladded non heat treatable AlMg aluminium alloys. Examples are novel cladded products intended for tank applications that show an improved performance with regard to the demands on strength, corrosion resistance and visual appearance. A further example is the use of cladded sheet products for applications were, next to other requirements, both strength and corrosion resistance are required. Also, developments in heat treatable AlMgSi body sheet alloys will be presented which show that in some cases a monolithic solution is available with a property mix that is competitive with were today a cladded solution is sometimes preferred. An example is a door inner applications were there is a simultaneous demand for high formability and good corrosion properties.
14:30-15:00 "The Future Generation Flaps for Coaches" - An intelligent Aluminium Hybrid Solution incorporating Sheet and Extruded Profiles
Tobias SchwalbManaging Director, apt Oehme GmbH, Eckental, Germany
Abstract
The Future Generation Flaps for Coaches by apt® is a key - example for the confirmation that Aluminium is the preferred metal for Lightweight Applicatitons in Automotive. This unique product is an intelligent Alumium Hybrid Solution incorporating Sheet and Extruded Profiles - innovative, flexible and ultra light produced within extreme short lead- time and using a highly automated one- piece- flow concept.
This by apt® designed, developed, engineered and fabricated product equates highest requirements in the dimensions: Physical / Functional / Appearance / Logistics / Costs.
The Future Generation Flaps for Coaches by apt® is a key - example for the confirmation that Aluminium is the preferred metal for Lightweight Applicatitons in Automotive. This unique product is an intelligent Alumium Hybrid Solution incorporating Sheet and Extruded Profiles - innovative, flexible and ultra light produced within extreme short lead- time and using a highly automated one- piece- flow concept.
This by apt® designed, developed, engineered and fabricated product equates highest requirements in the dimensions: Physical / Functional / Appearance / Logistics / Costs.
15:00-15:30 Novelis multi-material-Fusion(TM) for the automotive concepts of the future
Dr. Rainer Kossak
Development Automotive, Novelis Switzerland SA, Sierre, Switzerland
Abstract
The Novelis multi-material approach which has become reality by the special Fusion casting technology allows to combine highest strength, improved formability, very good bendability and superior corrosion performance. The contribution of aluminium to the realisation of light weight concepts is well known and thus helps to reduce fuel consumption and CO2 emissions. But up to now most of the applications of aluminium are restricted to hang-on parts in the front area like motor hoods and fenders. The Fusion material allows a technological break-through. It combines properties which are normally contradictory e.g. high strength and good bendability or very good formability of high Mg containing alloys and superior corrosion performance against intergranular corrosion attack. The first applications of Fusion have already been adopted for series production: the door inners - traditionally a domain of good formable steel because of the complexity of the part - of the BMW 7series model are stamped out of Fusion AF350. The 2nd generation of extremely good formable Fusion variants is under evaluation and qualification for various projects. The other important property for the application in the BIW is strength. Aluminium will not enter into the competition with super high strength steels of more than 800 MPa for the yield stress. But Fusion allows to reach strength levels of 330 to 350 MPa in service which are equivalent to steels of 500 MPa. About 60 % of the steel applications in new models have strength levels below 500 MPa and only 15 - 20 % are above 600 MPa. Despite the necessary increase in gauge by 50 % you still will save weight up to 40 % in structural applications. Regarding the coming European legislation for CO2 emissions all car manufacturers will be forced to use all options to avoid the real expensive penalties for exceeding these limits. The full strength potential of aluminium in the T6 temper could be used for e.g roll forming applications with moderate forming requirements. The cost issue of aluminium is adressed by high strength alloy versions which allow the downgauging of skin sheet applications like fenders to thicknesses below 0.9 mm which is an improvement of more than 10% for nearly all of the car manufacturers. FusionTM will help to keep our environment cleaner and thus makes the individual mobility "greener".
The Novelis multi-material approach which has become reality by the special Fusion casting technology allows to combine highest strength, improved formability, very good bendability and superior corrosion performance. The contribution of aluminium to the realisation of light weight concepts is well known and thus helps to reduce fuel consumption and CO2 emissions. But up to now most of the applications of aluminium are restricted to hang-on parts in the front area like motor hoods and fenders. The Fusion material allows a technological break-through. It combines properties which are normally contradictory e.g. high strength and good bendability or very good formability of high Mg containing alloys and superior corrosion performance against intergranular corrosion attack. The first applications of Fusion have already been adopted for series production: the door inners - traditionally a domain of good formable steel because of the complexity of the part - of the BMW 7series model are stamped out of Fusion AF350. The 2nd generation of extremely good formable Fusion variants is under evaluation and qualification for various projects. The other important property for the application in the BIW is strength. Aluminium will not enter into the competition with super high strength steels of more than 800 MPa for the yield stress. But Fusion allows to reach strength levels of 330 to 350 MPa in service which are equivalent to steels of 500 MPa. About 60 % of the steel applications in new models have strength levels below 500 MPa and only 15 - 20 % are above 600 MPa. Despite the necessary increase in gauge by 50 % you still will save weight up to 40 % in structural applications. Regarding the coming European legislation for CO2 emissions all car manufacturers will be forced to use all options to avoid the real expensive penalties for exceeding these limits. The full strength potential of aluminium in the T6 temper could be used for e.g roll forming applications with moderate forming requirements. The cost issue of aluminium is adressed by high strength alloy versions which allow the downgauging of skin sheet applications like fenders to thicknesses below 0.9 mm which is an improvement of more than 10% for nearly all of the car manufacturers. FusionTM will help to keep our environment cleaner and thus makes the individual mobility "greener".
15:30-16:00 Rolling of Aluminium Riblet-Surfaces
M.Sc. T. Romans
Institute of Metal Forming, RWTH Aachen, Germany
Abstract
A surface that is inscribed with riblets (series of microscopic grooves) exhibits a reduced frictional drag. It is a principle first observed while studying sharks. In the ocean these animals rely on their riblet-skin to make them more energy efficient. For aerodynamicdriven applications too the principle shows great prospective. The energy efficiency of objects moving at high-speeds and having substantial friction to pressure drag-ratios can be improved. In other words their fuel consumption is lowered, which in itself implies a direct cost relief upon application. If a turbulent flow surrounds a body, it decelerates the object. The applications of ribs parallel to the flow direction prevent the vortexes of the turbulent flow to ‘stick’ to the surface, resulting in a lower frictional drag.
A surface that is inscribed with riblets (series of microscopic grooves) exhibits a reduced frictional drag. It is a principle first observed while studying sharks. In the ocean these animals rely on their riblet-skin to make them more energy efficient. For aerodynamicdriven applications too the principle shows great prospective. The energy efficiency of objects moving at high-speeds and having substantial friction to pressure drag-ratios can be improved. In other words their fuel consumption is lowered, which in itself implies a direct cost relief upon application. If a turbulent flow surrounds a body, it decelerates the object. The applications of ribs parallel to the flow direction prevent the vortexes of the turbulent flow to ‘stick’ to the surface, resulting in a lower frictional drag.