AA6061-T6의 NaCl 수용액중에서의 S.C.C.연구 = A Study on the S.C.C. of AA6061-T6 in NaCl Solution

다국어 초록 (Multilingual Abstract)

Stress corrosion cracking may be defined as the spontaneous failure of a metal resulting from the combined effect of corrosion and stress.
Particularly, under the specific corrosive environments contained chloride and sulphide, high strength steels and alloys are very susceptible to stress corrosion cracking.
Accordingly, in this investigation, the stress corrosion cracking characteristics in the aluminum alloy AA6061-T6 sheet for the various percents NaCl solution environments wens studied.
Experiments were conducted with the symmetric double edge cracked specimens at 80℃ and the various percentages of 5%, 10%, 15% and 20% in experimental room temperature.
In order to accelerate the tests, 0.35% H_2O_2 was added to the NaCl solutions.
The results obtained are as follows:
(1) AA6061-T6 sheet in 5%, 10%, 15% and 20% NaCl solutions at 80℃, S.C.C. was occurred and according to rise the percents of NaCl solutions, incubation period was delayed and the crack growth rats was accelerated. In all cases, the crack propagation in the directions approximately perpendicular to the applied tensile stress.
(2) S.C.C. behaviors in rte Log d(2a)/dt vs. K_1 relation curves provide a full representation ion I , region II and region III.
(3) K_1S. c.c. value is defined around 39kg·mm^-3/2 for the AA6061-T6 sheet.
(4) K_1c value is defined around 50kg·mm^-3/2 for the AA6061-T6 sheet.
(5) The relation of d(2a)/dt vs. K_1 for region II is as follows: d(2a)/dt = C·10^mk1.
The value of constant m is found 8.19 x 10 exp(-2).