High Temperature Creep Deformation Mechanism and Time Hardening Model of Glass Fiber Reinforced Polypropylene
The creep resistance of materials is closely related to the strength,stiffness,and dimensional changes of products under long-term service,which is an important research direction for the applications and developments of lightweight technology.To investigate the creep deformation mechanism and time hardening model of glass fiber reinforced polypropylene materials(PP-GF30s),PP-GF30s were prepared into standard dumbbell shaped splines under certain injection molding conditions.The creep performance tests were carried out via a creep testing machine,characterizing the sample high-temperature creep behaviors.The results show that the tensile strength and modulus of PP-GF30s at high temperatures exhibit a linear trend with temperature,and the failure mode evolves from fiber fracture to interface failure.High temperature creep deformation includes general elastic deformation,high elastic deformation,and viscous flow.The general elastic deformation and high elastic deformation increase linearly with creep stress,and recover after the external force is removed.Viscous flow and creep stress exhibit exponential growth,and deformation cannot recover after the external force is removed.The time hardening correction model is εc=Aσncta+bσc.The effect of creep stress on the time index is corrected,and the system accuracy is greatly improved.
Glass Fiber Reinforced PolypropyleneCreepViscoelasticityTime Hardening ModelTime Index
万方数据
维普
