Vigilancia tecnológica

Five groups of three?point bending tests of wood plastic composites (WPCs) at different temperatures were conducted. The test temperatures ranged from ?40 to 40°C, and the temperature difference of each group was 20°C. The results show that the bending strength and elastic modulus of the specimens decrease continuously with increasing temperature. Twenty?four?hour bending creep tests of WPCs under a 50% stress level were completed at different temperatures. The Findley model predicted the short?term creep of WPCs better. According to the results of the short?term creep tests, the horizontal shift factor was introduced based on the Prony series model. Then, we proposed a formula for creep compliance over time at different temperatures to predict the long?term creep performance of WPCs under a 50% stress level at different temperatures. The results indicate that when the test temperature is less than 0°C, WPCs can hold the load for 50?years without entering the tertiary creep stage; at 20°C, the WPC specimen will fail at 24?days, whereas at 40°C, the specimen can only last for 24?h and then enters the tertiary creep stage until fracture damage occurs.