Improvement of compressive strength and ductility in NiAl–Cr(Nb)/Dy alloy by rapid solidification and HIP treatment

2012 ◽  
Vol 27 ◽  
pp. 14-20 ◽  
Author(s):  
L.Y. Sheng ◽  
F. Yang ◽  
T.F. Xi ◽  
Y.F. Zheng ◽  
J.T. Guo
2021 ◽  
Vol 81 ◽  
pp. 219-228
Author(s):  
Zhong-Zheng Jin ◽  
Min Zha ◽  
Hai-Long Jia ◽  
Pin-Kui Ma ◽  
Si-Qing Wang ◽  
...  

2007 ◽  
Vol 539-543 ◽  
pp. 5031-5036
Author(s):  
Dong Geun Lee ◽  
Yont Tai Lee ◽  
Jong Taek Yeon ◽  
Jeoung Han Kim ◽  
Nho Kwang Park ◽  
...  

Dynamic compressive tests were conducted on Zr-based amorphous alloys and amorphous matrix composite containing dendritic β phases. Dynamic compressive tests were conducted using a compressive Kolsky bar and then the test data were analyzed in relation to microstructure and fracture mode. Under dynamic loading, the maximum shear stress and ductility of the amorphous alloy and composite were considerably lower than those under quasi-static loading because of the decreased resistance to fracture. Deformation under dynamic loading lowered strain and compressive strength because of reduced fracture resistance, and the alloy containing dendritic β phases showed better compressive strength and ductility than the monolithic alloy.


Author(s):  
Farhad Behnamfar ◽  
Hadi Rafizadeh ◽  
Mortza Omidi

This research work presents new details for moment connections in precast concrete structures satisfying both design and practice criteria. In this paper the results of the numerical study on the connections are presented. For the analysis, the ANSYS software is selected because of its diversity in nonlinear analysis. By calculating the monotonic load-displacement curve of each connection, the connections are evaluated for their stiffness, strength, and ductility. The compressive strength of the connection concrete is taken to be 30, 35 and 40 MPa, for each round of analysis. The results of the analysis show that the proposed connections are stiff enough to be moment resisting and to be emulating an equivalent monolithic, or basic connection. It is illustrated that the connections are stronger but somewhat less ductile than the basic connection regardless of the concrete strengths examined. Moreover, it is shown that in each precast connection while increasing the compressive strength of concrete does not affect the connection stiffness considerably, it increases the ultimate load and ductility of the connection. As a main result of this study, the suggested connection details are categorized based on their stiffness, strength, and ductility. The suggested connections can be used in moment resisting precast concrete buildings based on the desired strength and ductility.


2014 ◽  
Vol 69 (3) ◽  
Author(s):  
Hoong-Pin Lee ◽  
Abdullah Zawawi Awang ◽  
Wahid Omar

An experimental and analytical study on the application of Steel Strapping Tensioning Technique (SSTT) confinement on twelve high-strength concrete cylinder specimens with dimension of 100 mm and 200 mm in diameter and height respectively has been studied and presented throughout this paper. The specimens were volumetric-identically confined with two different confining materials of different mechanical properties and lateral pre-tensioning stresses, namely SSTT(HC) and SSTT(SS). All concrete specimens were tested under uniaxial compression load. The performance of SSTT-type confined specimens were studied through their stress-strain relationship upon the longitudinal and transverse deformation, mode of failure, level of lateral pre-tensioning stress, and dilatancy behaviour. The results show that high-strength concretes confined with SSTT would significantly reduce the brittleness problem and at the same time, enhancing both ultimate compressive strength and ductility up to 65% and 344%, 36% and 269% for both SSTT(HC) and SSTT(SS), respectively. Those specimens confined with higher lateral pre-tensioning stress exhibits smaller radial expansion and higher rate of axial strain, able to slow down the dilation of confined specimens under loading and thus, helps in enhancing the compressive capacity and ductility. In addition, an analytical comparison between SSTT-type confinement and conventional confinement models have been presented and the results show a linear relationship between the compressive strength enhancement and confinement ratio. Current experimental results were also validated by comparing the observed stress-strain relationship proposed by Mander. 


2011 ◽  
Vol 130-134 ◽  
pp. 1621-1625
Author(s):  
Hua Xin Liu ◽  
Dong Ming Wang

The technology of GFRP has received significant attentions in civil engineering due to their unique properties, such as high strength-to-weight radio, good resistance to corrosion and fatigue, convenient to construction and no additional dimension. Study the properties of GFRP confining concrete column through eight groups of columns subjected to axial loading, the effect of width of straps and spacing of straps of GFRP sheets confining concrete column is analyesed. The results are the axial compressive strength and ductility of concrete prism wrapped by GFRP sheets or GFRP straps have all increased to a certain degree, the process of destruction of concrete prism wrapped by GFRP become slower than common concrete prism.


Sign in / Sign up

Export Citation Format

Share Document