A Study on the Corrosion Behaviour of Aluminium Alloy 2014 T-651 Friction Stir Welds Using Stress Corrosion Cracking

Author(s):  
Thamilarasan Kollapuri ◽  
Madhanagopal Manoharan ◽  
Rajendra Boopathy Sadayan ◽  
Rama Koteswara Rao Sajja

Stress Corrosion Cracking (SCC) is the initiation and slow growth of cracks under the influence of tensile stresses and aggressive corrosion environment. Al alloy 2014 T 651 was solution heat treated and stress-relieved. In the present work, Stress Corrosion Cracking (SCC) experimental arrangement has been used to test the severity of aluminium alloys under particular environmental conditions. Sound welds were obtained with Friction Stir Welding at rotational speed of 800 rpm and welding speed of 200 mm/min. Friction Stir Welds were cut into standard tensile specimens as per ASTM E8 standards. Time to failure of the welds were obtained using 3.5 wt% NaCl solution at pH 10 in 0.7 and 1.1 yields by Stress Corrosion Cracking. Vickers micro-hardness was taken along various regions of the weld. Optical micro-graphs and scanning electron fractographs were taken to analyse the fracture behavior and fracture morphology of Friction Stir Welded aluminium alloy specimens, subjected to Stress Corrosion Cracking.

2018 ◽  
Vol 54 (5) ◽  
pp. 866-875
Author(s):  
G. Srinivasa Rao ◽  
K. Srinivasa Rao ◽  
P. Srinivasa Rao ◽  
S. R. Koteswara Rao ◽  
G. Madhusudan Reddy

2017 ◽  
Vol 26 (3-4) ◽  
pp. 105-112
Author(s):  
P. Prabhuraj ◽  
S. Rajakumar ◽  
A.K. Lakshminarayanan ◽  
V. Balasubramanian

AbstractThe objective of the present study is to determine the threshold stress level of stress corrosion cracking (SCC) in AA7075-T651 aluminium alloy by suitable experimentation. The test was carried out using a circumferential notch specimen in a horizontal-type constant load SCC setup in a 3.5 wt.% NaCl solution. The time to failure by SCC was determined at various loading conditions. The threshold stress of AA7075-T651 alloy was found to be 242 MPa in a 3.5 wt.% NaCl solution. The various regions of the fractured surface specimen such as machined notch, SCC region and final overload fracture area were examined using scanning electron microscopy (SEM) in order to identify the SCC mechanism.


CORROSION ◽  
1973 ◽  
Vol 29 (6) ◽  
pp. 251-260 ◽  
Author(s):  
W. R. WEARMOUTH ◽  
G. P DEAN ◽  
R. N. PARKINS

2010 ◽  
Vol 438 ◽  
pp. 155-162 ◽  
Author(s):  
Panayotis Spathis ◽  
Efthimios Papastergiadis ◽  
Georgios Stalidis ◽  
Georgios Papanastasiou

Aim of the present work is the study of corrosion and stress corrosion cracking behaviour of 1050 Al-Alloy anodised in a 3M H2SO4 anodising bath with the presence in it of malonic acid, in various concentrations and anodising current densities. The investigation was carried out by SCC (Stress Corrosion Cracking) tests and electrochemical measurements. The influence of applied potential on SCC behaviour was also examined. The corrosion and SCC behaviour of anodised 1050 Al-Alloy was found to vary with malonic acid concentration, anodising conditions, applied potential and stress level. In SCC conditions all prepared coatings protected the bare alloy, with better protective properties in the case of 0.015M concentration of malonic acid prepared with a 6 A.dm-2 anodising current density. The coating prepared in these conditions had better mechanical properties as indicated from the increased protection at a high stress level and also the better behaviour in corrosion, without stress, conditions of coatings prepared in different conditions of malonic acid concentration and anodising current density. For the interpretation of the results, properties of the anodic coatings as thickness, packing density, coating ratio, roughness, were also studied. The anodic coating formed in a electrolytic bath of 0.015M concentration of malonic acid and a 6 A.dm-2 anodising current density was found to be less porous, more compact and rough, with better oxide structure. Prepared coatings were found to increase protective properties in an area of applied potentials slightly more anodic than the free corrosion potential values.


2012 ◽  
Vol 557-559 ◽  
pp. 127-130 ◽  
Author(s):  
Xiao Fei Yao ◽  
Fa Qin Xie ◽  
Xiang Qing Wu ◽  
Yi Fei Wang

Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results showed that super 13Cr tubing steel has good properties of resistance stress corrosion cracking in acidic medium, effects of pH value on super13Cr tubing steel resistance stress corrosion was not very obviously in the acidic medium, with pH value decreased, super 13Cr tubing steel tensile strength decreased, elongation rate decreased, fracture area contraction ratio decreased, break time reduced, the tendency of the stress corrosion cracking increased. the stress corrosion cracking susceptibility index kσ and kε were all increasing, that increased degree of kε were obviously than kσ, effects of pH value on the plastic deformation of super 13Cr tubing steel were greater than tensile strength.


2015 ◽  
Vol 67 (4) ◽  
pp. 352-360 ◽  
Author(s):  
C. Natividad ◽  
R. García ◽  
V. H. López ◽  
R. Galván-Martínez ◽  
M. Salazar ◽  
...  

Metals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 578 ◽  
Author(s):  
C. Panagopoulos ◽  
Emmanuel Georgiou ◽  
K. Giannakopoulos ◽  
P. Orfanos

In this work, the effect of pH (3, 7 and 10) on the stress corrosion cracking behavior of 6082 aluminum alloy, in a 0.3 M sodium chloride (NaCl) aqueous based solution was investigated. The stress corrosion cracking behavior was studied with slow strain rate testing, whereas failure analysis of the fractured surfaces was used to identify the dominant degradation mechanisms. The experimental results clearly indicated that stress corrosion cracking behavior of this aluminum alloy strongly depends on the pH of the solution. In particular, the highest drop in ultimate tensile strength and ductility was observed for the alkaline pH, followed by the acidic, whereas the lowest susceptibility was observed in the neutral pH environment. This observation is attributed to a change in the dominant stress corrosion cracking mechanisms.


1991 ◽  
Vol 113 (1) ◽  
pp. 125-129 ◽  
Author(s):  
P. S. Pao ◽  
R. A. Bayles ◽  
G. R. Yoder

The presence of small ripple loading can, under certain circumstances, significantly reduce time-to-failure and threshold stress intensity for stress-corrosion cracking (SCC) of steels. A predictive framework for such ripple-loading effects (RLE) is developed from concepts and descriptors used in SCC and corrosion fatigue characterization. The proposed framework is capable of defining critical conditions required for the occurrence of RLE and predicting the time-to-failure curves. The agreement between the predicted and laboratory data is excellent.


1990 ◽  
Vol 38 (9) ◽  
pp. 1619-1623 ◽  
Author(s):  
M. Yamashita ◽  
M. Yoshioka ◽  
T. Mimaki ◽  
S. Hashimoto ◽  
S. Miura

Sign in / Sign up

Export Citation Format

Share Document