碳纤维增强PEEK树脂基复合材料的单轴时相关循环特性实验研究

摘要

The uniaxial time dependent cyclic of carbon fiber/polyether ether ketone（PEEK） composite was studied experimentally. The volume fraction of carbon fiber was 30% The property under stress control led and stress- controlled loading and the ratcheting behaviors of carbon fiber/PEEK composite were discussed under different conditions. It was shown that the creep behavior of carbon fiber/PEEK composite is better than that of PEEK. In the experiment of strain- controlled cyclic, the stress amplitude has a close relationship with the applied strain loading rate and strain amplitude. Due to the stress relaxation, the responded stress amplitude will decreases as the hold time at strain peak increase. The ratcheting occurs in the composite to asymmetrical stress-controlled, and the ratcheting strain depends on the stress amplitude and stress loading rate. The stress holding time and low loading rate lead to an increased ratcheting strain. The carbon fiber will fail as the peak holding time beyond the range.%通过对碳纤维／PEEK复合材料（纤维体积分数30％）的单调拉伸、应力控制循环、应变控制循环实验，对该材料的应力、应变循环特性以及棘轮行为的率相关、时相关特性进行了系统的研究。研究表明：与PEEK树脂基体材料相比，加入碳纤维使材料的抗蠕变性能有所提高。在应变控制循环实验中，响应应力幅值与应变加载速率和应变加载幅值密切相关；在应力松弛效应的影响下，响应应力幅值随着应变峰值保持时间的增加而减小。室温下，碳纤维／PEEK复合材料在非对称应力循环中产生明显的棘轮应变，并且对加载应力幅值和平均应力具有明显的依赖性，此外，当在较低的加载速率和具有一定峰值保持时间情况下，棘轮应变显著增强。