mme.modares.ac.ir
1
*
2
1 -
2 -
* 13114
- 16846 [email protected]
22 :
1393 1393 10 :
: 11 1393
.
.
SBT 9244AL2024-T3
.
30 60 90 100
. %
.
. .
-
Numerical study of the effect of moisture–induced swelling stresses on damage behavior of adhesive joints under static loading
Hadi Khoramishad
*Zahra Abbasi
Department of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran
*P.O.B. 16846-13114 Tehran, Iran,[email protected]
A RTICLE I NFORMATION A BSTRACT
Original Research Paper Received 13 November 2014 Accepted 31 December 2014 Available Online 31 January 2015
The main limitation of the use of adhesive joints is susceptibility of the adhesive layer to damaging environmental factors such as humidity. Use of numerical methods for predicting the strength of adhesive joints exposed to moist environment can save significant amount of time and cost. In this study, first, experimental investigation and numerical modeling of the complete process of moisture diffusion into the adhesive layer and its damaging effect on the adhesive joint strength were determined. Then this process was applied for single lap joint of SBT 9244 pressure sensitive adhesive and AL2024-T3 aluminum alloy substrate with two 12.5 and 50 mm overlap of lengths. In the irst step, moisture distribution for 30, 60 and 90 days exposure time in environmental condition of 100% relative humidity was obtained. Then single lap joint tensile test was simulated using cohesive zone model for different exposure times. In this simulation cohesive zone model parameters were determined in such way that numerical failure load and the existing experimental failure load were in good agreement. The cohesive zone model parameters were determined depending on the moisture content. The first simulation was done without considering swelling and in the second, swelling was considered. Swelling stress was obtained separately at different exposure time periods. It was found that swelling effect was more considerable in the joints with longer overlap length and shortened exposure time.
Keywords:
Adhesivejoints Moisture Swelling
cohesive zone model environmental degradation
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8 -
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