滚动过程中聚四氟乙烯、聚酰胺66、聚醚型聚氨酯的弹性滞后效应与本构关系的研究

基于标准线性固体本构模型，从弹性滞后效应的角度推导了滚动摩擦系数的表达式。利用试验机、轮廓摩擦磨损仪考察了聚四氟乙烯（PTFE）、聚酰胺66(PA66)、聚醚型聚氨酯（PEUR）的蠕变、松驰行为，求出相关参数；在滚动摩擦实验台上考察了PTFE、PA66和PEUR等塑料轮子与铸铁HT200配副在不同载荷、速度下的滚动摩擦行为，讨论了材料的黏弹性与滚动摩擦系数间的耦合关系。结果表明,3种聚合物试样的滚动摩擦系数均随速度的增加而增大；相同实验条件下，PEUR、PA66和PTFE的滚动摩擦系数比约为1.12∶1.02∶1；理论计算结果与实验数据相一致，表明弹性滞后效应是塑料滚动过程中摩擦阻抗的主要来源。

Elastic Hysteric Effect and Constitutive Model of PTFE,PA66 and Polyester-type TPU Under Rolling Contact

The rolling friction coefficient was theoretically deduced from the elastic hysteric effect according to the standard linear solid model. The static creep and relaxation characteristics of PTFE, PA66 and polyester-type TPU(PEUR) was evaluated by a CETR UMT-2 type equipment and an LKDM-2000 tester, and their rolling friction behavior under different loads and velocities was investigated by a rolling friction testing equipment. The coupling relationship between the viscoelasticity and rolling friction coefficient was discussed through a comparison between experimentals data and theoretical results. The results indicated that the rolling friction coefficient of the three polymers increased with an increase of the rolling velocities. The ratio of rolling friction coefficient for PEUR, PA66 and PTFE was 1.12∶1.02∶1 under the same experimental condition. The theoretical data of the rolling friction coefficient were consistent with the experimental results, indicating that the friction resistance force was mainly originated from the elastic hysteresis effect.