Werden gewichtsoptimiert konstruierte Bauteile durch die Verwendung von Leichtmetallen wirklich leichter?*)
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Peter Neumann
Abstract
In der Verkehrstechnik und vielen anderen technischen Bereichen bringt Leichtbau ökonomische und ökologische Vorteile. Daher werden Werkstoffe zunehmend nach ihrem Leichtbaupotential beurteilt. Im Falle der Strukturwerkstoffe, die gewissen Belastungen standhalten müssen, ist allerdings eine Einteilung nach der Dichte („Leichtmetalle‘‘) ungenügend. Der entscheidende Parameter ist vielmehr das Verhältnis von Dichte zu Festigkeit. Im Falle der Biegebeanspruchung wird der Sachverhalt kompliziert, da z. B. die elastische Steifigkeit solcher Bauteile (bei gegebener Länge) nicht nur von ihrem Volumen, sondern auch von ihrer Gestalt abhängt. In dieser Arbeit wird gezeigt, dass der übliche Vergleich von unterschiedlichen Werkstoffen zum Zwecke der Beurteilung ihres Leichtbaupotentials einseitig die weicheren Werkstoffe bevorzugt. Wenn dagegen der Vergleich unter der Bedingung vergleichbarer Außendimensionen gemacht wird, zeigt sich, dass ein und derselbe Parameter für einsinnigen Zug als auch für Biegebeanspruchungen gilt. Damit wird klar, dass das Leichtbaupotential von hochfesten Stählen und Aluminiumlegierungen vergleichbar ist – nicht nur unter einsinnigem Zug, sondern auch unter Biegebeanspruchungen.
Abstract
In transportation and many other technologies weight reduction brings about economical and environmental advantages. Therefore, materials are increasingly judged according to their weight saving potential. In the case of structural materials, which have to withstand given stresses, a classification based on specific gravity alone (“light metals”) falls short. The crucial parameter is the ratio between density and strength. In the case of parts loaded in bending the situation is complicated by the fact that e. g. the elastic stiffness of such parts (of a given length) does not only depend on their volume but also on their shape. It is shown in this paper that the usual comparison of different materials under bending loads to obtain the weight saving potential is strongly shape biased, favoring the more compliant material. If the comparison is made under the condition of equal external dimensions, the same merit parameter, which applies for uni-axial tension, also applies for parts loaded in bending. As a result it is becomes obvious that the weight saving potential of high strength steels and aluminium alloys are comparable – not only in uni-axial tension but also in bending.
Literatur
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© 2002 Carl Hanser Verlag, München
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- Notifications/Mitteilungen
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- Books/Bücher
- DGM Conferences/Training
Articles in the same Issue
- Frontmatter
- Editorial
- Editorial
- Articles/Aufsätze
- A model for the work hardening of WC–Co “hard metals”
- On the dispersion strengthening mechanisms in ODS materials
- Effect of hydrogen on the mechanical properties of the β titanium alloy Timetal® 21S
- Cyclic deformation behaviour of (α + β) titanium alloys under complex mechanical and physiological loading conditions
- Assessment of the influence of interdendritic shrinkage cavities on the thermo-mechanical fatigue behaviour of the nickel-base superalloy MAR-M247LC
- Effects of static strain aging on residual stress stability and alternating bending strength of shot peened AISI 4140
- On the possibilities to enhance the fatigue properties of ultrafine-grained metals
- New method of determining stress relaxation behavior in creep machines by controlled unloading
- Creep of binary Ni-rich NiTi shape memory alloys and the influence of pre-creep on martensitic transformations
- Interaction of high-cycle fatigue with high-temperature creep in superalloy single crystals
- A unified description of creep in pure and dispersion-strengthened copper
- A new interpretation of flow-stress measurements of high-purity NiAl below room temperature
- A mesoscopic plasticity model accounting for spatial fluctuations of plastic strains, internal stresses and dislocation densities
- Behavior of X-ray peak widths in the Wilkens model of a restrictedly random distribution of dislocations
- Dislocation structure and crystallite size distribution in hexagonal nanomaterials from X-ray peak profile analysis
- Werden gewichtsoptimiert konstruierte Bauteile durch die Verwendung von Leichtmetallen wirklich leichter?*)
- Strain-induced martensite formation in metastable austenitic steels with varying carbon content
- Isothermal bainitic transformation in low alloy steels: factors limiting prediction of the resulting material’s properties
- Fatigue damage evolution in a particulate-reinforced metal matrix composite determined by acoustic emission and compliance method
- Microstructure and modification mechanisms of Si phase in as-thixoformed alloy A356
- Influence of size effect on microstructural changes in cyclically deformed polycrystalline nickel
- Self-diffusion of 71Ge and 31Si in Si –Ge alloys
- On localised corrosive attack, stress corrosion cracking and corrosion fatigue effects in a hardmetal cutting-tool material
- The internal stress during growth of SiC single crystals
- Notifications/Mitteilungen
- Personal/Personelles
- Books/Bücher
- DGM Conferences/Training
