The effect of loading direction on the dwell fatigue properties of Ti-6Al-4V forged bar with highly oriented texture

The purpose of this study was to improve our understanding of the effect of macro/micro texture on dwell fatigue properties. The Ti-6Al-4V forged bar with highly oriented texture and fine equiaxed microstructure was used. Dwell fatigue, cyclic fatigue and creep tests were conducted at room temperature by using specimens taken in the longitudinal (L) direction and the transverse (T) direction of the bar. The effects of loading direction on dwell fatigue life and fracture surface morphology were examined in detail. The dwell fatigue life in T direction was shorter than that in L direction. The fracture surface morphologies were characteristically varied by loading waveform, amplitude and directions. In the range of 93 - 95% of 0.2%PS, the characteristic large facets were observed in the T direction in dwell fatigue. Detailed analyses revealed that the large facet consists of multiple initiation facets and propagation facets. The propagation facet plane and crack propagation direction appeared to correspond to alpha (0001) <10-10>. Furthermore, the relationship between strain rate and life time was compared to that for room temperature creep. The deviation from the Monkman-Grant relationship corresponded to the change of the fracture surface morphology.

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Mechanical Properties of 5052 Al Alloy Processed by Groove Pressing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.468-471.1831 ◽

2012 ◽

Vol 468-471 ◽

pp. 1831-1835

Author(s):

Kai Huai Yang ◽

Na Lin ◽

Shao Feng Zeng ◽

Wen Zhe Chen

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Fracture Surface ◽

Surface Morphology ◽

Fracture Mode ◽

Room Temperature ◽

Al Alloy ◽

Fracture Surface Morphology ◽

Annealed State

Three groups of commercial 5052 Al alloy sheets were subjected to groove pressing (GP) at room temperature using parallel GP, 180° cross GP and 90° cross GP, respectively. Mechanical properties and fracture modes of as-annealed and GPed samples were investigated. The microhardness of the samples processed by parallel GP increases by a factor of about 1.6 compared to the as-annealed state, and that of the samples processed by cross GP is higher. The ultimate tensile strength (UTS) increases significantly after GP, while the elongation decreases. But they are strongly dependence on the number of GP passes and the pressing modes. Besides, fracture surface morphology demonstrates that the fracture mode is ductile even after four passes. With increasing the number of GP pass, the amount of small dimples increases, and the dimples become shallow and more uniform.

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Study of the fracture surface morphology of impact and tensile tested cast and forged (C&F) Grade 91 steel at room temperature for different heat treatment regimes

Engineering Failure Analysis ◽

10.1016/j.engfailanal.2016.06.012 ◽

2017 ◽

Vol 71 ◽

pp. 131-147 ◽

Cited By ~ 59

Author(s):

Chandan Pandey ◽

Nitin Saini ◽

Manas Mohan Mahapatra ◽

Pradeep Kumar

Keyword(s):

Heat Treatment ◽

Fracture Surface ◽

Surface Morphology ◽

Room Temperature ◽

Fracture Surface Morphology ◽

Treatment Regimes ◽

Grade 91 ◽

Heat Treatment Regimes ◽

Grade 91 Steel

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Effect of peanut and walnut shells powders on tensile properties and morphological test by using heat cured PMMA as a matrix for prosthetic Denture

Engineering and Technology Journal ◽

10.30684/etj.v39i2a.1730 ◽

2021 ◽

Vol 39 (2A) ◽

pp. 196-205

Author(s):

Zainab M. Abdul Monem ◽

Jawad K. Oleiwi ◽

Qahtan A. Hamad

Keyword(s):

Fracture Surface ◽

Surface Morphology ◽

Matrix Material ◽

Weight Fraction ◽

Fracture Surface Morphology ◽

Ductile Materials ◽

Walnut Shells ◽

Peanut Shells ◽

The Matrix ◽

Material Powder

In the current Research , the heat cured matrix material powder of PMMA was reinforced with peanut and walnut shells (natural powders) which are chemically treated with 5% (w/v) (NaOH) to improve the matrix bonding (PMMA) before being used as a reinforcing powder and adding to exactly similar averages particle sizes ≤ (53µm), with different weight fractions of (4, 8, and 12 wt.%). The ASTM D638 is used for composite specimens of the tensile test. The results indicated that the Elastic modulus values reached its maximum value at (8 wt.%.) when reinforced with peanut shells particles (1.053Gpa) , while ,the values of tensile strength, elongation percentage at break, decrease as the weight fraction of peanut and walnut shells powder increase and the lowest values is obtained by reinforcing with peanut shells particles to reach their minimum values at (12 wt.%.) where the lowest values of them are (29 MPa, 2.758% ) respectively. The fracture surface morphology of pure PMMA seemed to be homogenous morphology in (SEM) test, whereas the fracture surface morphology of PMMA composite reinforced by (peanut and walnut shells) powders and shows a roughness fracture surface morphology this refer to semi ductile to ductile materials.

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Influence of Different Surface Treatments on Fatigue Life of 7050 Al Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.944.142 ◽

2019 ◽

Vol 944 ◽

pp. 142-148 ◽

Cited By ~ 4

Author(s):

Nan Li ◽

Hai Tao Li ◽

Jing Yi Zhou ◽

Hong Tao Liu ◽

Chang Kui Liu ◽

...

Keyword(s):

Residual Stress ◽

Fatigue Life ◽

Fracture Surface ◽

Surface Morphology ◽

Surface Analysis ◽

Shot Peening ◽

Surface Treatments ◽

Al Alloy ◽

Stress Measurements ◽

Fracture Surface Analysis

The fatigue life of 7050 Al alloy samples after different surface treatments, i.e., as-machined, anodizing, shot peening, and shot peening followed by anodizing, had been tested. The shot peening treatment specimens presented the longest average fatigue life. The fatigue life of anodizing treatment specimens decreased by 69.3% and 78.8% at 215 MPa and 260 MPa stress levels than as-machined ones. Introducing the shot peening treatment before anodizing can increase the fatigue life by 220% / 296.9% at 215 MPa/260 Mpa than that only treated by anodizing. The effect of the surface treatments on the fatigue life were studied by performing surface morphology investigation, residual stress measurements and fracture surface analysis.

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Research on Fracture Surface Morphology and Tensile Properties of Cellulose-Based Green Food Packaging Membrane Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.469.148 ◽

2013 ◽

Vol 469 ◽

pp. 148-151

Author(s):

Zhi Jian Li ◽

Qing Jun Meng

Keyword(s):

Tensile Strength ◽

Fracture Surface ◽

Surface Morphology ◽

Food Packaging ◽

Fracture Surface Morphology ◽

Strength Performance ◽

Green Food ◽

Phase Inversion Technique ◽

Performance Research ◽

Membrane Strength

The Green food-packaging membranes were prepared with N-methylmorpholine-N-oxide (NMMO) as the major solvent by using L-S phase inversion technique. Scanning electron microscopy (SEM) was adopted to characterize fracture surface morphology of membrane, and tensile machine was adopted to test the membrane strength performance. Research results show with the concentration of cellulose increases from 5% to 9%, structure of membrane becomes compact, aperture size becomes small and even, value of tensile strength increases 59.6%, and value of elongation increases 67.5%. With dissolving temperature increases from 100°C to 120°C, structure of membrane becomes loose, pore size becomes big and uneven, value of tensile strength decreases 19.2%, and value of elongation decreases 13.1%. The research can provide the theoretical reference for optimizing technology, adjusting the structure of membrane, and improving the performances of membrane.

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