scholarly journals Mechanical properties and fatigue of extruded D16 alloy profiles of the Al-Cu-Mg system after ion irradiation

2021 ◽  
Vol 2144 (1) ◽  
pp. 012024
Author(s):  
N V Gushchina ◽  
V V Ovchinnikov ◽  
K V Shalomov ◽  
D I Vichuzhanin
Keyword(s):  
Mechanical Properties ◽  
Ion Irradiation ◽  
Natural Aging ◽  
Maximum Increase ◽  
Low Load ◽  
Number Of Cycles ◽  
Cycles To Failure

Abstract The effect of 20-keV Ar+ ion irradiation on the mechanical properties andfatigue resistance of 6 mm thick hot-extruded profiles made of a D16 alloy (Al–Cu–Mg system) has been studied after natural aging. Irradiation at fluences of 2.1015 cm−2 and 1.1016 cm−2 has been revealed to increase the number of cycles to failure significantly at low load amplitudes σ/σu = 0.3. The maximum increase in the number of cycles to destruction 2.4 times is observed at a smaller fluence of ions F = 2.1015 cm−2.

Microstructure and Properties Characterization of Polycrystalline Ni-Fe-Cr-Based Superalloy EP-718E after Electric Upsetting

2016 ◽  
Vol 721 ◽  
pp. 467-472 ◽  
Author(s):  
Lembit Kommel
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Energy Dispersive Spectrometry ◽  
Fatigue Testing ◽  
Tension Stress ◽  
Tension Testing ◽  
Electric Upsetting ◽  
Number Of Cycles ◽  
Cycles To Failure

The purpose of this study is to analyze the effect of electric upsetting on the microstructure defects eliminating and mechanical properties evolution of the Ni-Fe-Cr-based polycrystalline superalloy EP718E. The microstructure was examined by scanning electron microscope and energy dispersive spectrometry techniques. The material mechanical properties were characterized by nanoindentation, by tension testing of micro samples and high cycle fatigue testing at room temperature. The results show, that the microstructure defects on confluence of grain boundaries (depending on the processing stages) were step-by-step eliminated. The tension stress was lowered but elongation was increase. As a result of such changes in microstructure and mechanical properties of alloy the fatigue strength (δ-1) was increased from δ-1 = 300 MPa to δ-1 = 540 MPa and the number of cycles to failure was increased from N1 = 2·107 up to N4 = 4 x (2·107), respectively.

Characterisation of the Mechanical Properties of MEMS Devices Using Nanoscale Techniques

2007 ◽  
Author(s):  
N. X. Randall
Keyword(s):  
Mechanical Properties ◽  
Mems Devices ◽  
Beam Structures ◽  
Coated Materials ◽  
Recent Developments ◽  
Silicon Structures ◽  
Number Of Cycles ◽  
Cycles To Failure ◽  
Depth Response

This presentation will focus on recent developments in the localized characterization of the mechanical properties of Microsystems and MEMS devices and structures. Conventional indentation techniques provide a highly powerful method for measuring the load and depth response of bulk and coated materials, but can also be used to measure the mechanical properties of very small micro-machined silicon structures. Beam structures, such as are used for accelerometers, need to be characterized in terms of the number of cycles to failure, the spring constant or the energy required to bend the beam by a required amount. Such localized testing needs to be adapted to work at various distances from the origin of the beam with a positioning accuracy of less than a micron. Initial studies have proved to be highly repeatable. A variety of examples are presented which cover a range of application areas, including accelerometer beam structures, micro-switches and printer head components. In addition, the localized testing of friction and wear in MEMS devices will be covered with some examples of the technology available and how it may be applied to such small contact areas in an accurate and reproducible way.

Characterisation of the mechanical properties of MEMS devices using nanoscale techniques

2002 ◽  
Vol 741 ◽  
Author(s):  
Nicholas X. Randall ◽  
Richard A. J. Soden
Keyword(s):  
Mechanical Properties ◽  
Mems Devices ◽  
Powerful Method ◽  
Beam Structures ◽  
Coated Materials ◽  
Recent Developments ◽  
Silicon Structures ◽  
Number Of Cycles ◽  
Cycles To Failure ◽  
Depth Response

ABSTRACTThis paper focuses on recent developments in the localised characterisation of the mechanical properties of Microsystems and MEMS devices and structures. Conventional indentation techniques provide a highly powerful method for measuring the load and depth response of bulk and coated materials, but can also be used to measure the mechanical properties of very small micro-machined silicon structures. Beam structures, such as are used for accelerometers, need to be characterised in terms of the number of cycles to failure, the spring constant or the energy required to bend the beam by a required amount. Such localised testing needs to be adapted to work at various distances from the origin of the beam with a positioning accuracy of less than a micron. Initial studies have proved to be highly repeatable. A range of examples is presented which covers a range of application areas, including accelerometer beam structures, microswitches and printer head structures. The basic instrumental concepts are explained together with the modifications required for testing small structures in a localised way.

Study of Micro-Mechanical Properties of Alloyed Surface with TiNi Layer Considering Shape Memory Effect

2014 ◽  
Vol 704 ◽  
pp. 22-26
Author(s):  
Zh.M. Blednova ◽  
P.O. Rusinov ◽  
I.S. Myshevsky
Keyword(s):  
Mechanical Properties ◽  
Shape Memory ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Shape Recovery ◽  
Mechanical Tests ◽  
Alloyed Surface ◽  
Number Of Cycles ◽  
Cycles To Failure

Mechanical tests of alloyed TiNi compounds with shape memory effect were performed. Low-cycle tests of alloyed compounds showed that an increase in the number of cycles to failure doubled. Studies conducted using the indentation showed shape recovery of print on material of alloyed weld within 0.7-1.2%.

Fatigue Life of the Human Teeth: A Continuum Damage Approach

2019 ◽  
Vol 43 ◽  
pp. 1-19
Author(s):  
Theddeus Tochukwu Akano
Keyword(s):  
Fatigue Life ◽  
Damage Mechanics ◽  
Stress Amplitude ◽  
Continuum Damage Mechanics ◽  
Continuum Damage ◽  
Elastoplastic Model ◽  
Human Teeth ◽  
Proposed Model ◽  
Number Of Cycles ◽  
Cycles To Failure

Normal oral food ingestion processes such as mastication would not have been possible without the teeth. The human teeth are subjected to many cyclic loadings per day. This, in turn, exerts forces on the teeth just like an engineering material undergoing the same cyclic loading. Over a period, there will be the creation of microcracks on the teeth that might not be visible ab initio. The constant formation of these microcracks weakens the teeth structure and foundation that result in its fracture. Therefore, the need to predict the fatigue life for human teeth is essential. In this paper, a continuum damage mechanics (CDM) based model is employed to evaluate the fatigue life of the human teeth. The material characteristic of the teeth is captured within the framework of the elastoplastic model. By applying the damage evolution equivalence, a mathematical formula is developed that describes the fatigue life in terms of the stress amplitude. Existing experimental data served as a guide as to the completeness of the proposed model. Results as a function of age and tubule orientation are presented. The outcomes produced by the current study have substantial agreement with the experimental results when plotted on the same axes. There is a notable difference in the number of cycles to failure as the tubule orientation increases. It is also revealed that the developed model could forecast for any tubule orientation and be adopted for both young and old teeth.

Study on the Formability of Aluminium Alloy Sheets at Room and Elevated Temperatures

2016 ◽  
Vol 877 ◽  
pp. 393-399
Author(s):  
Jia Zhou ◽  
Jun Ping Zhang ◽  
Ming Tu Ma
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Elevated Temperature ◽  
Aluminium Alloy ◽  
Aluminium Alloys ◽  
Elevated Temperatures ◽  
Hot Stamping ◽  
Natural Aging ◽  
Alloy Sheet ◽  
Aluminum Alloy Sheet

This paper presents the main achievements of a research project aimed at investigating the applicability of the hot stamping technology to non heat treatable aluminium alloys of the 5052 H32 and heat treatable aluminium alloys of the 6016 T4P after six months natural aging. The formability and mechanical properties of 5052 H32 and 6016 T4P aluminum alloy sheets after six months natural aging under different temperature conditions were studied, the processing characteristics and potential of the two aluminium alloy at room and elevated temperature were investigated. The results indicated that the 6016 aluminum alloy sheet exhibit better mechanical properties at room temperature. 5052 H32 aluminum alloy sheet shows better formability at elevated temperature, and it has higher potential to increase formability by raising the temperature.

Percolation Effects in the Mechanical Properties of Granular Ni-A12O3 thin films

1990 ◽  
Vol 195 ◽  
Author(s):  
T.E. Schlesinger ◽  
A. Gavrin ◽  
R.C. Cammarata ◽  
C.-L. Chien
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Plastic Deformation ◽  
Magnetic Properties ◽  
Percolation Threshold ◽  
Volume Fraction ◽  
Electrical And Magnetic Properties ◽  
Low Load

ABSTRACTThe mechanical properties of sputtered Ni-Al2O3 granular thin films were investigated by low load microharaness testing. It was found that the microhardness of these films displayed a percolation threshold at a nickel volume fraction of about 0.6, below which the hardness is greatly enhanced. This behavior is qualitatively similar to the electrical and magnetic properties of these types of films. A percolation threshold in hardness can be understood as due to a change in the mechanism for plastic deformation.

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