Mechanical Properties Testing of Diamond and Diamond-Like Films by Ultra-Low Load Indentation

Author(s):  
Michael E. O’Hern ◽  
Carl J. McHargue
1990 ◽  
Vol 195 ◽  
Author(s):  
T.E. Schlesinger ◽  
A. Gavrin ◽  
R.C. Cammarata ◽  
C.-L. Chien

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.


2011 ◽  
Vol 314-316 ◽  
pp. 1210-1213
Author(s):  
Fang Po Li ◽  
Yong Gang Liu ◽  
Wang Yong

The failure cause of Φ127mm G105 IEU drill pipe upset was investigated through mechanical properties testing, optical morphologies and fracture surface analysis. The result show that drill pipe upset’s failure reason is the elephant hide and decarburization layer in its out-surface caused by improper upset treatment in forging process. Elephant hide and decarburization layer existing in drill pipe upset changed seriously reduced its strength and fatigue property. Under the effect of alternating stresses, the crack first initiated from the deepest position of elephant hide and developed quickly. In the end, it leaded the drill pipe to early piecing failure.


2013 ◽  
Vol 318 ◽  
pp. 331-335
Author(s):  
Hong Zhang ◽  
Quan Luo ◽  
Xu Hui Liu ◽  
Peng Wang ◽  
Ding Feng

The 13-3/8〞casing of a well was bent down and broken off in the marine development completion process. The cause for the fracture is systematically analyzed by means of chemical composition analysis, mechanical properties testing, macro and micro fracture analysis and metallographic analysis. The results indicate that, the heterogeneity of the casing material and large oxide metallurgical inclusions found in fracture place severely reduce the properties of the material, which lead to the failure of casing pipe in bad service environment.


2019 ◽  
Vol 795 ◽  
pp. 340-345
Author(s):  
Luo Wei Cao ◽  
Guo Shan Xie ◽  
Min Zhen Zhao

Failure analysis of the hot clamped outlet pigtail tubes connected with hydrogen reformer tube in refineries has been carried out. In this paper, hot clamp induced cracking on Incoloy 800HT outlet pigtail tube of a reformer unit is studied by microscopic observation and mechanical properties testing. Metallurgical evaluation and chemical composition analysis have been performed on both hot clamped cracking tube and no cracking one. Results indicated that the most important parameter affecting the high temperature brittleness of pigtails are the Ni/Cr value, surface grain size and impurity atoms grain boundary segregation.


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