Effects of Relative Humidity and Temperature on Creep Parameters of Medium Density Fiberboard (MDF)

In this research، creep behavior of medium density fiber board (MDF) under different conditions (different relative humidity and different temperature) was investigated. For this purpose، flexural creep tests at 15% and 30% of ultimate bending load were performed by using flexural creep equipment. The samples underwent under load at relative humidity of 45، 65 and 85% and temperatures of 15، 23 and 30°C for 72 hours. The results showed that relative creep and total creep of the samples increase with increasing temperature and relative humidity، while the creep modulus decreases with increasing temperature and relative humidity. The greater changes were obtained at higher relative humidity and temperature an also at higher load level. The results also showed that the relative creep is more sensitive to relative humidity compared to temperature. Conversely creep modulus is more sensitive to temperature compared to relative humidity that greater changes have been observed in higher load level.