Three Ways of Sampling and Fatigue Test Results of Steel P92

2014 ◽  
Vol 891-892 ◽  
pp. 273-277
Author(s):  
Josef Volák ◽  
Zbynek Bunda
Keyword(s):  
Mechanical Properties ◽  
Power Plant ◽  
Fatigue Test ◽  
Fatigue Tests ◽  
Energy Industry ◽  
Fatigue Properties ◽  
Test Results ◽  
Steam Turbines ◽  
Standard Samples ◽  
Energy Component

This paper describes the fatigue properties of the steel P92. This material is widely used in the energy industry, especially for pipes and pipe bends of supercritical steam turbines. Steel P92 is alloyed with 2 % of tungsten compared to steel P91. This increases a creep strenght of the material. It is possible to reduce wall thickness of the P92 pipe up to about 20%. Fatigue tests were carried out on standard samples and compared with SFT samples (Small Fatigue Test). Using the device SSam 2 made by company Rolce Royce, it is possible to gently remove a samples from energy component without power plant shutdowns. Consider these correlations, i tis possible to determine mechanical properties of the material from small amount of removed experimental material.

Comparison of P92 Steel Fatigue Test Results in Relation to Specimen Size and Manufacturing

2013 ◽  
Author(s):  
Josef Volak ◽  
Zbynek Bunda ◽  
Vaclav Mentl
Keyword(s):  
Fatigue Test ◽  
Positive Influence ◽  
Fatigue Tests ◽  
Energy Industry ◽  
Fatigue Properties ◽  
Strength Increase ◽  
Test Results ◽  
Steam Turbines ◽  
Standard Samples ◽  
P92 Steel

This paper describes fatigue properties of steel P92. This material is used as a standard in the energy industry, especially for production of pipes and flange branches and distance pieces of supercritical steam turbines. This material contains (unlike material P91) up to 2% of tungsten which has positive influence on creep strength increase. Compared to the P91 material, it is possible to reduce wall thickness of the P92 pipe up to 20%. Fatigue tests were carried out on standard samples and compared with SFT samples (Small Fatigue Test). SFT samples can be gently withdrawn from energy component by SSam 2 device made by company Rolls Royce. There is no necessity for shutdown of power plant. Thanks to the existing correlations between SFT and Fatigue tests, it is possible to determine mechanical properties of material from a small amount of withdrawn material. At the same time a comparison between a traditional way of sample production and a sample production by means of waterjet cutting was carried out.

Frequency Effects on Gigacycle Fatigue Properties of High-Strength Steels

2004 ◽  
Author(s):  
Yoshiyuki Furuya ◽  
Saburo Matsuoka ◽  
Takayuki Abe
Keyword(s):  
Fatigue Test ◽  
Testing Machine ◽  
High Strength Steels ◽  
High Strength ◽  
Fatigue Tests ◽  
Fatigue Properties ◽  
Test Results ◽  
Frequency Effects ◽  
Fracture Region ◽  
Fish Eye

This report will reveal a series of fatigue test results for high-strength steels at 100 Hz and 20 kHz and discuss frequency effects on gigacycle fatigue properties. The 20 kHz fatigue testing machine is an effective tool to conduct gigacycle fatigue tests in a reasonable term, while frequency effects have to be carefully investigated before applying the machine. The fatigue tests were conducted for two kinds of high-strength steels, that were a low-alloy steel and a spring steel. These fatigue test results showed that the frequency effects were negligible even at 20 kHz in case of fish-eye fracture. The fatigue properties in the fish-eye fracture region showed a good agreement between the 100 Hz and 20 kHz tests. Besides, ODAs (Optically Dark Areas) were also observed on the fracture surface even in 20 kHz tests and no difference was found in the ODA sizes between the 100 Hz and 20 kHz tests. These results meant that the 20 kHz tests could provide us appropriate results at least in the fish-eye fracture region. Therefore, the 20 kHz tests were applicable on the evaluation of gigacycle fatigue properties in high-strength steels.

scholarly journals Analysis of the Correlation between the Static and Fatigue Test Results of the Interlayer Bondings of Asphalt Layers

2016 ◽  
Vol 62 (1) ◽  
pp. 83-98 ◽  
Author(s):  
A. Szydło ◽  
K. Malicki
Keyword(s):  
Fatigue Life ◽  
Fatigue Test ◽  
Asphalt Mixture ◽  
Fatigue Tests ◽  
Test Results ◽  
Static Tests ◽  
Bonding State ◽  
Road Pavement ◽  
The Future ◽  
Pavement Structure

Abstract The bonding state of the asphalt layers in a road pavement structure significantly affects its fatigue life. These bondings, therefore, require detailed tests and optimization. In this paper, the analyses of the correlation between the results of laboratory static tests and the results of fatigue tests of asphalt mixture interlayer bondings were performed. The existence of the relationships between selected parameters was confirmed. In the future, the results of these analyses may allow for assessment of interlayer bondings’ fatigue life based on the results of quick and relatively easy static tests.

Cyclic Mechanical Properties of 16MnR Welded Joint under Constant

2011 ◽  
Vol 197-198 ◽  
pp. 1658-1661
Author(s):  
Ying Xiong ◽  
Han Ying Zheng
Keyword(s):  
Mechanical Properties ◽  
Weld Metal ◽  
Endurance Limit ◽  
Welded Joint ◽  
Cyclic Softening ◽  
Fatigue Tests ◽  
Test Results ◽  
Control Test ◽  
Strain Control ◽  
Fatigue Endurance

Fatigue tests are carried out for 16MnR welded joint under constant strain control. Test results reveal that 16MnR weld metal exhibits characteristic of cyclic softening and non-masing obviously. The strain–life curve can be best described by the three-parameter equation. It shows the fatigue endurance limit in the heat-affecting zone (HAZ) of welded joint is lower than that in the weld metal.

scholarly journals Development in mechanical and fatigue properties of AA6061/AL2O3 nanocomposites under stirring temperature (ST)

2021 ◽  
Vol 4 (12(112)) ◽  
pp. 47-52
Author(s):  
Raad Mohammed Abed ◽  
Ali Yousuf Khenyab ◽  
Hussain Jasim M. Alalkawi
Keyword(s):  
Mechanical Properties ◽  
Cost Effective ◽  
Fatigue Tests ◽  
Core Material ◽  
Fatigue Properties ◽  
Uniform Distributions ◽  
Al2o3 Composite ◽  
Structural Applications ◽  
The Matrix ◽  
High Fatigue

Aluminum is expected to remain the core material for many critical applications such as aircraft and automobiles. This is due to the high resistance to different environmental conditions, desired and manageable mechanical properties, as well as high fatigue resistance. Aluminum nanocomposites such as AA6061/Al2O3 can be made in many ways using a liquid metallurgy method. The main challenges for this method in the production of nanocomposites are the difficulties of achieving a uniform distribution of reinforcing materials and possible chemical reactions between the reinforcing material and the matrix. For structural applications exclusive to aerospace sectors. The growing cost-effective nanocomposites mass production technology with essential operational and geometric flexibility is a big challenge all the time. Each method of preparing AA6061/Al2O3 nanocomposites can provide different mechanical properties. In the present study, nine nanocomposites were prepared at three stirring temperatures (800, 850, and 900 °C) with the level of Al2O3 addition of 0, 5, 7, and 9 wt %. The results of tensile, hardness and fatigue tests revealed that the composite including 9 wt % Al2O3 with 850 °C stirring temperatures has the best properties. It was also revealed that the 850 °C stirring temperature (ST) with 9 wt % Al2O3 composite provide an increase in tensile strength, VHN and reduction in ductility by 20 %, 16 % and 36.8 % respectively, compared to zero-nano. Also, the fatigue life at the 90 MPa stress level increased by 17.4 % in comparison with 9 wt % nanocomposite at 800 °C (ST). Uniform distributions were observed for all nine microstructure compositions.

Fatigue Properties of 3D Welded Thin Structures

2020 ◽  
Author(s):  
Seyed M. Allameh ◽  
Avery Lenihan ◽  
Roger Miller ◽  
Hadi Allameh
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Fatigue Testing ◽  
Interfacial Area ◽  
Tensile Tests ◽  
Orientation Dependence ◽  
Fatigue Tests ◽  
Fatigue Properties ◽  
Mig Welding ◽  
Welded Structures

Abstract Additive manufacturing technology has matured enough to produce real industrial components. A newer method of 3D printing is the deposition of molten metal beads using a MIG weld torch. This involves a 3D printer equipped with a MIG torch layering the metals in desired shapes. It allows the fabrication of components made of MIG weld wires, currently available from various elements including Cu, Al, steel and alloys. Some of these structures made by 3D welding will have applications in critical load bearing conditions. The reliability of such components will be vital in applications where human lives are at stake. Tensile tests are conducted to verify the required strength of the fabricated parts which will undergo monotonic loading; however, fatigue tests are required for cases where cyclic loading will take place. Conventional tensile and fatigue testing requires macro-scale samples. With MIG welding, it is possible to make thin-walled structures. Fatigue testing on samples extracted from thin walls is made possible by microtesting. This study is focused on the mechanical properties of 3D welded structures made from MIG welding wires. Our earlier results showed orientation dependence of mechanical properties in 3D welded structures. They also showed the effect of substrates in expression of the orientation dependence. Welding on metal substrate produces weld beads that are harder at the substrate interfacial area. However, for structures welded on ceramics, the opposite is true. They exhibit a softer substrate interfacial area and a relatively harder top. Our newer results show fatigue properties of structures made by 3D welding. Microsamples measuring 0.2 mm × 0.2 mm × 1.0 mm were extracted from metal beads using a CNC mill along with an EDM. The contours of the samples were machined by milling and the back side was cut by electro discharge machining. Specimens were then polished to the desired size and mounted in the grippers of an E1000 Instron load frame. WaveMatrix® application software from Instron was used to control the machine and to obtain testing data. Fatigue tests were performed, and life cycles were determined for various stress levels up to over 5 million cycles. The preliminary results of tensile tests of these samples show strength levels that are comparable to those of parent metal, in the range of 600–950MPa. Results of fatigue tests show high fatigue lives associated with relatively high stresses. The preliminary results will be presented and the implications of the use of 3D welded rebar in 3D printing of reinforced concrete structures will be discussed.

Fatigue Properties of Al-Li Plates Joined by Friction Stir Welding

2008 ◽  
Vol 385-387 ◽  
pp. 849-852 ◽  
Author(s):  
Pasquale Cavaliere ◽  
Francesco W. Panella ◽  
Antonio Squillace
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Testing Machine ◽  
Rolling Direction ◽  
Tensile Tests ◽  
Fatigue Tests ◽  
Control Mode ◽  
Fatigue Properties ◽  
Amplitude Control ◽  
Friction Stir

Al-Li alloys are characterized by a strong anisotropy in mechanical properties and microstructure with respect to the rolling direction. Plates of 2198 Al-Li alloy were friction stir welded by employing maximum rotation speed: 1000 rev/min and welding speed of 80 mm/min, both in parallel and orthogonal directions with respect to the rolling one. The joints mechanical properties were evaluated by means of tensile tests at room temperature. In addition, fatigue tests performed with a resonant electro-mechanical testing machine under constant amplitude control up to 250 Hz loading, were conducted in axial control mode with R(σmin/σmax)=0.33, for all the welding and rotating speed conditions. The fatigue crack propagation experiments were performed by employing single edge notched specimens.With the aim to characterize the weld performances, both the microstructure evolution at jointed cross sections, related to the welding variables, and the fractured surfaces were respectively analyzed by means of optical and scanning electron microscopy.

Comparison Between ASME Code-Case N-761, NUREG/CR-6909 and Stainless Steel Component Fatigue Test Results

2014 ◽  
Author(s):  
H. T. Harrison ◽  
Robert Gurdal
Keyword(s):  
Stainless Steel ◽  
Fatigue Test ◽  
Fatigue Tests ◽  
Test Series ◽  
Test Results ◽  
Actual Number ◽  
Steel Component ◽  
Class 1 ◽  
Asme Code ◽  
Number Of Cycles

For Class 1 components, the consideration of the environmental effects on fatigue has been suggested to be evaluated through two different methodologies: either NUREG/CR-6909 from March 2007 or ASME-Code Case N-761 from August 2010. The purpose of this technical paper is to compare these two methods. In addition, the equations from Revision 1 of the NUREG/CR-6909 will be evaluated. For these comparisons, two stainless steel component fatigue test series with documented results are considered. These two fatigue test series are completely different from each other (applied cyclic displacements vs. insurge/outsurge types of transients). Therefore, they are producing an appropriate foundation for these comparisons. In general, the severities of the two methods are compared, where the severity is defined as the actual number of cycles from the fatigue tests, including an evaluation of the scatter, divided by the number of design cycles from the two methods. Also, how stable the methods are is being evaluated through the calculation of the coefficient of variation for each method.

scholarly journals Using Fatigue Characteristics to Analyse Test Results for 16Mo3 Steel under Tension-Compression and Oscillatory Bending Conditions

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1197 ◽  
Author(s):  
Andrzej Kurek
Keyword(s):  
Compression Test ◽  
Experimental Tests ◽  
Fatigue Tests ◽  
Test Method ◽  
Fatigue Properties ◽  
Test Results ◽  
Bending Tests ◽  
Fatigue Characteristics ◽  
Cost Efficient ◽  
Plastic Components

In this study, 16Mo3 steel was analysed for fatigue tests under tension-compression and oscillatory bending conditions. The analysis involved a comparison of fatigue test results obtained using the Manson-Coffin-Basquin, Langer and Kandil models and the models proposed by Kurek-Łagoda. It was observed that it is possible to substitute the basic tension-compression test performed in large testing machines with oscillatory bending tests carried out on a simple, modern test stand. The tests were performed under oscillatory bending on a prototype machine. The testing of 16Mo3 steel proved that the best-known Mason-Coffin-Basquin fatigue characteristic describes the results of all of the experimental tests very well, but the model can only be used when it is possible to divide strains into elastic and plastic components. It should be emphasised here that there is no such possibility in the case of tests performed under oscillatory bending conditions. It was proven that the proposed test method can substitute the tension-compression test very well and be a much more cost efficient way to obtain LCF material fatigue properties.

Effect of Pre-Strain on Fatigue Properties of NHH Rail

2004 ◽  
Vol 261-263 ◽  
pp. 1239-1244
Author(s):  
Wen Xian Sun ◽  
S. Nishida ◽  
Nobusuke Hattori ◽  
X.L. Yue
Keyword(s):  
Fatigue Crack ◽  
Fatigue Strength ◽  
Fatigue Test ◽  
Fatigue Cracks ◽  
Fatigue Tests ◽  
Fatigue Properties ◽  
Slip Lines ◽  
Propagation Behavior ◽  
Strain Process ◽  
Initiation And Propagation

In the present study, fatigue tests have been performed to study the effect of pre-strain on fatigue properties of NHH (New Head-Hardened) rail. The objectives of this study were: (1) to observe the microscopic behavior of specimens during pre-strain process, (2) to research the influence of pre-strain on fatigue strength of NHH rail and (3) to investigate initiation and propagation behavior of the fatigue crack. The results showed that plastic pre-strain decreased the fatigue strength of NHH rail; fatigue limits had no obvious variation among the different pre-strain ratios. Fatigue cracks initiated in the microscopic cracking or slip lines that were originated in the pre-strain process and propagated from these sites in the later fatigue test.

Sign in / Sign up

Export Citation Format

Share Document