Evaluation of static fatique and cyclic fatique performances of foams, upholstered furniture

In this thesis, the performances of polyurethane foams, with 6 different densities and two different categories, produced in Karadeniz Region were evaluated by static fatigue and cyclic fatigue tests. The foams were first subjected to IFD tests. Then the foams were subjected to static and cyclic tests. Then, the IFD's of the foams were measured and the changes in the IFD's were determined. Cyclic tests were conveyed in a pneumatic test system by applying loads according to ASTM D 3574. The changes in the thicknesses of foams and the relationship between density and firmness of foams were investigated. Results showed that, in general, the effect of cyclic test on foam performances was greater than the static test. Results of cyclic test, a linear proportion between density and firmness in normal foams was observed, but no linearity was observed for soft foams. While the difference between the losses of firmness obtained in procedures B and A is not statically significant in normal foams, the loss of firmness in procedure B is greater than the one in procedure A for soft foams. Long term usage lets firmness loss in soft foams. At the end of static tests, when the density increased in normal foams, the loss rate in firmness decreased. However, this was opposite for the soft foams.