Fracture Behavior of Directional TiAl Lamellar Structures

2011 ◽  
Vol 488-489 ◽  
pp. 634-637
Author(s):  
Ji Zhang
Keyword(s):  
Tensile Properties ◽  
Fracture Behavior ◽  
Detrimental Effect ◽  
Lamellar Microstructure ◽  
Griffith Crack ◽  
Lamellar Structures ◽  
Technology Improvement

In order to assess the influences of macro- and microstructure as well as the cast flaw on the tensile properties, the fracture behavior of a number of ambient tensile TiAl specimens containing directional lamellar microstructure have been analyzed. It is found that all the fractures of tensile specimens are triggered by a critical Griffith crack. According to the desirable ambient tensile properties coincide with the initial cracking facets smaller than 600 mm, it is proposed that the detrimental effect of the random oriented lamellar colonies on the tensile properties can be eliminated through cast technology improvement.

scholarly journals Polylactic acid (PLA) based green composites reinforced pineapple leaf fibres: evaluation of processing and tensile performance

2018 ◽  
Vol 192 ◽  
pp. 03002
Author(s):  
Jedsada Chaishome ◽  
Suriyan Supapvanich
Keyword(s):  
Tensile Properties ◽  
Polylactic Acid ◽  
Detrimental Effect ◽  
Process Variables ◽  
Compression Moulding ◽  
Stiffness Modulus ◽  
Vacuum Forming ◽  
Tensile Performance ◽  
The Matrix ◽  
Consolidation Temperature

This paper reports on a study of the compression moulding and the vacuum forming of unidirectional pineapple leaf fibres/polylactic acid composites and the influence of process variables on the tensile properties of the material. The characterisation of the micro and meso structures of the pineapple leaf fibres is reported. The effect of consolidation temperature on the fibre thermal stability and the tensile properties of the composites is investigated. The results show that vacuum forming was found to be preferable process with high stiffness modulus and UTS of the composites, compared to compression moulding. The insignificant detrimental effect of 165°C high consolidation temperature was observed. Finally, the fibre thermal degradation seems to dominate the composite tensile performance over its interfacial quality between the fibre and the matrix.

Mechanical Properties and Fracture Behavior of Indirect Squeeze-Cast A354 Alloy Using Local Pressurization

2016 ◽  
Vol 850 ◽  
pp. 502-510
Author(s):  
Hai Jun Liu ◽  
Lie Jun Li ◽  
Jian Wei Niu ◽  
Ji Xiang Gao ◽  
Xue Wen Chen
Keyword(s):  
Mechanical Properties ◽  
Tensile Properties ◽  
Fracture Behavior ◽  
Eutectic Silicon ◽  
Solidification Rate ◽  
Fracture Morphology ◽  
Shrinkage Cavity ◽  
Squeeze Cast ◽  
Ductile Mode ◽  
Eutectic Si

The effect of local pressurization on mechanical properties and fracture behavior of indirect squeeze-cast A354 alloy has been investigated. As compared to conventional process, the porosity and shrinkage cavity for heavy sectioned squeeze castings were improved by the indirect squeeze casting, while its tensile properties were inferior to other parts of the casting. That is mainly due to that inhomogeneous eutectic Si particles within strip, angular and fragment shapes distribute in bulky α-Al cells, which is caused by slower solidification rate. After T6 treatment, the fragmentation and spheroidization of the eutectic silicon happened. Under this situation, the effect of fragmentation on α-Al matrix reduced. Tensile properties of the casting (both local pressurization part and non-local pressurization part) were enhanced greatly, by 36.8% and 25.4%, respectively. Fracture analysis results show that the type of fracture morphology is changed from mixed mode of brittle cleavage and ductile to ductile mode after T6-treatment.

Effect of hydrogen on tensile properties and fracture behavior of PH 13-8 Mo steel

2016 ◽  
Vol 108 ◽  
pp. 608-617 ◽  
Author(s):  
Xinfeng Li ◽  
Jin Zhang ◽  
Yanfei Wang ◽  
Sicong Shen ◽  
Xiaolong Song
Keyword(s):  
Tensile Properties ◽  
Fracture Behavior

Tensile Properties and Deformation-Fracture Behavior of Ti-6Al-4V Alloy at Cryogenic Temperature

2007 ◽  
Vol 561-565 ◽  
pp. 207-210 ◽  
Author(s):  
Shang Li Dong ◽  
Y.C. Xin ◽  
G. Lu ◽  
D.Z. Yang ◽  
S.Y. He ◽  
...  
Keyword(s):  
Tensile Properties ◽  
Cryogenic Temperature ◽  
Fracture Behavior ◽  
Room Temperature ◽  
Testing Temperature ◽  
Alloy Sheet ◽  
Dislocation Slip ◽  
Solution Treated ◽  
Dominant Deformation Mechanism ◽  
Specimen Orientation

Tensile properties and deformation-fracture behavior at temperatures ranging from 123K to 293K of a Ti-6Al-4V alloy sheet with a thickness of 1.5mm has been studied, and the effects of testing temperature, specimen orientation and heat-treatment were investigated. An increase in strength and a decrease in fracture strain were found with decreasing tension temperature, and the anisotropy in tensile properties was observed at room and cryogenic temperatures both in the annealed and solution treated and aged (STA) specimens. TEM examinations indicated that plastic deformation occurred within both α and β phases in the STA specimens testing at either room or cryogenic temperature. The dominant deformation mechanism varied from dislocation slip at room temperature to twinning at 123K. SEM observations showed that the amount of dimples and tearing grains on fractured surfaces of the specimens decreased as testing temperature was decreased.

Sign in / Sign up

Export Citation Format

Share Document