Influence of the stress gradient on the fatigue life calculation of a martensitic high strength steel

2017 ◽  
Author(s):  
Igor Miloševi ◽  
Gerhard Winter ◽  
Florian Grün ◽  
Martin Kober
Keyword(s):  
High Cycle Fatigue ◽  
Stress Gradient ◽  
High Strength ◽  
Complex Stress ◽  
The Other ◽  
Stress Distributions ◽  
Cycle Fatigue ◽  
Different Types ◽  
The One ◽  
Gradient Approach

Nowadays lifetime calculation in the high cycle fatigue region is commonly based on S/N curves which are modified by different influences to ensure accurate results. Especially the application of these models is important when small components with complex stress distributions are used. The influence of the stress distribution was considered by the stress gradient approach which is implemented in the lifetime tool FEMFAT. Specimens with diameters of D4mm and D7.5mm were used to examine the effect of the calculation modified by the stress gradient. On the one hand regarding different types of this approach it can be shown that the results fit very well compared to the testing results but on the other hand a big difference was observed when the gradient increases by smaller specimen sizes.

Plausibility and Aesthetic Interpretation

1977 ◽  
Vol 7 (2) ◽  
pp. 327-340 ◽  
Author(s):  
Denis Dutton
Keyword(s):  
Scientific Inquiry ◽  
The Other ◽  
Inquiry Science ◽  
Works Of Art ◽  
Different Types ◽  
Logical Structures ◽  
The One

If a catalogue were made of terms commonly used to affirm the adequacy of critical interpretations of works of art, one word certain to be included would be “plausible.” Yet this term is one which has received precious little attention in the literature of aesthetics. This is odd, inasmuch as I find the notion of plausibility central to an understanding of the nature of criticism. “Plausible” is a perplexing term because it can have radically different meanings depending on the circumstances of its employment. ln the following discussion, I will make some observations about the logic of this concept in connection with its uses in two rather different contexts: the context of scientific inquiry on the one hand, and that of aesthetic interpretation on the other. In distinguishing separate senses of “plausible,” I shall provide reason to resist the temptation to imagine that because logical aspects of two different types of inquiry—science and criticism—happen to be designated by the same term, they may to that extent be considered to have similar logical structures.

On the critical inclusion size of high strength steels under ultra-high cycle fatigue

2006 ◽  
Vol 427 (1-2) ◽  
pp. 167-174 ◽  
Author(s):  
Z.G. Yang ◽  
J.M. Zhang ◽  
S.X. Li ◽  
G.Y. Li ◽  
Q.Y. Wang ◽  
...  
Keyword(s):  
High Cycle Fatigue ◽  
High Strength Steels ◽  
High Strength ◽  
Inclusion Size ◽  
Cycle Fatigue ◽  
Ultra High Cycle Fatigue

High Cycle Fatigue Resistance and Reliability Assessment of Flexible Printed Circuitry

2002 ◽  
Vol 124 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Elena Martynenko ◽  
Wen Zhou ◽  
Alexander Chudnovsky ◽  
Ron S. Li ◽  
Larry Poglitsch
Keyword(s):  
Fatigue Resistance ◽  
High Cycle Fatigue ◽  
Failure Mechanisms ◽  
Three Dimensional ◽  
Reliability Assessment ◽  
Core Layer ◽  
High Strength ◽  
Multiple Cracks ◽  
Material System ◽  
Cycle Fatigue

Flexible printed circuitry (FPC) is a patterned array of conductors supported by a flexible dielectric film made of high strength polymer material such as polyimide. The flexibility of FPC provides an opportunity for three dimensional packaging, easy interconnections and dynamic applications. The polymeric core layer is the primary load bearing structure when the substrate is not supported by a rigid plate. In its composite structure, the conductive layers are more vulnerable to failure due to their lower flexibility compared to the core layer. Fatigue data on FPCs are not commonly available in published literature. Presented in this paper is the fatigue resistance and reliability assessment of polyimide based FPCs. Fatigue resistance of a specific material system was analyzed as a function of temperature and frequency through experiments that utilized a specially designed experimental setup consisting of sine servo controller, electrodynamic shaker, continuity monitor and temperature chamber. The fatigue characteristics of the selected material system are summarized in the form of S-N diagrams. Significant decrease in fatigue lifetime has been observed due to higher displacements in high cycle fatigue. Observed temperature effect was however counter-intuitive. Failure mechanisms are discussed and complete fracture analysis is presented. In various FPC systems, it has been found that the changes take place in FPC failure mechanisms from well-developed and aligned single cracks through the width at low temperature to an array of multiple cracks with random sizes and locations at high temperature.

On effect of hydrogen on very high cycle fatigue behaviours of high strength steels

2013 ◽  
Vol 29 (11) ◽  
pp. 1290-1296 ◽  
Author(s):  
J-B Shi ◽  
Y D Li ◽  
W M Guo ◽  
N Xu ◽  
X F Wu ◽  
...  
Keyword(s):  
High Cycle Fatigue ◽  
High Strength Steels ◽  
High Strength ◽  
Cycle Fatigue ◽  
Very High Cycle Fatigue ◽  
Very High

Posthuman oder Übermensch. War Nietzsche ein Transhumanist?

2013 ◽  
Vol 42 (1) ◽  
Author(s):  
Michael Skowron
Keyword(s):  
Genetic Manipulation ◽  
Linguistic Analysis ◽  
The Other ◽  
The Internet ◽  
Jürgen Habermas ◽  
Eternal Recurrence ◽  
Different Types ◽  
The Future ◽  
The One ◽  
Michael Sandel

AbstractRecent discussions (especially in the Internet) about the question whether Nietzsche was a Transhumanist or at least a forerunner of the Transhumanist movement have drawn new attention to Nietzsche’s concept of the Overhuman and the relation to the Posthuman. The article is taking a critical stance by turning suggested analogies between education and genetic manipulation of humans into an argument against the latter, by relating self-education to self-overcoming and eternal recurrence of the same (which is excluded by Transhumanists), and by reminding of Nietzsche’s distinction between ‘Overhuman’ and ‘last human’ as two different ways to the future. Linguistic analysis of the epitheta used in speaking of the different ‘types’ in question as well as structural analogies between critical considerations in Michael Sandel and Jürgen Habermas on the one hand, Nietzsche on the other are also evidence that Nietzsche would not have endorsed the technological path to perfection of the human but would emphasize his own way of self-overcoming instead.

High Cycle Fatigue Behavior of Recycled Additive Manufactured Electron Beam Melted Titanium Ti6Al4V

2020 ◽  
Author(s):  
Melody Mojib ◽  
Rishi Pahuja ◽  
M. Ramulu ◽  
Dwayne Arola
Keyword(s):  
Electron Beam ◽  
Fatigue Life ◽  
Rough Surface ◽  
High Cycle Fatigue ◽  
Fatigue Behavior ◽  
High Strength ◽  
Fatigue Tests ◽  
Cycle Fatigue ◽  
Initiation And Propagation ◽  
Powder Recycling

Abstract Metal Additive Manufacturing (AM) has become a popular method for producing complex and unique geometries, especially gaining traction in the aerospace and medical industries. With the increase in adoption of AM and the high cost of powder, it is critical to understand the effects of powder recycling on part performance to move towards material qualification and certification of affordable printed components. Due to the limitations of the Electron Beam Melting (EBM) process, current as-printed components are susceptible to failure at limits far below wrought metals and further understanding of the material properties and fatigue life is required. In this study, a high strength Titanium alloy, Ti-6Al-4V, is recycled over time and used to print fatigue specimens using the EBM process. Uniaxial High Cycle Fatigue tests have been performed on as-printed and polished cylindrical specimens and the locations of crack initiation and propagation have been determined through the use of a scanning electron microscope. This investigation has shown that the rough surface exterior is far more detrimental to performance life than the powder degradation occurring due to powder reuse. In addition, the effects of the rough surface exterior as a stress concentration is evaluated using the Arola-Ramulu. The following is a preliminary study of the effects powder recycling and surface treatments on EBM Ti-6Al4V fatigue life.

Multichannel Modality in Displaying Information

2013 ◽  
Vol 4 (1) ◽  
pp. 60-79 ◽  
Author(s):  
Elisa Benetti ◽  
Gianluca Mazzini
Keyword(s):  
Computer Science ◽  
Public Administration ◽  
The Other ◽  
Public Institution ◽  
Automated System ◽  
Government Services ◽  
Physical Location ◽  
The Past ◽  
Different Types ◽  
The One

Computer science and telecommunications are increasingly important in society and this leads also public administrations to take advantage of ICT, in order to communicate with citizens in a more rapid and simpler way than the complex and paper-based bureaucracy of the past. While on the one hand the use of these technologies responds to the duty of any public institution to involve the largest number of addressees, on the other hand, society must also consider the limitations of these technologies. Firstly not everybody is so familiar in their use. Moreover, the digital administration thus becomes virtual, accessible only through technological devices and not present in a physical location, and is therefore essential to ensure full coverage of the territory, which is currently not always possible. The main novelty of this paper is the implementation of an automated system capable of adapting different types of government services to multiple communication media. The joint exploitation of multiple technologies allows to use the strengths of one of them when are found the limits of another, making this multichannel modality the solution to the requirement of ICT in public administration.

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