Characterization of Thermal-Mechanical Fatigue Responses of Structural Materials under Multiaxial Strain Cycling

9215694 Zamrik将使用两种结构材料进行一系列多轴热机械疲劳（疲劳）试验：316型不锈钢和镍基高温合金Waspaloy。 将在连续循环模式下进行循环试验，并对连续循环波形施加应变保持/温度。 保持期施加在连续加载循环中，以诱导时间依赖性效应，例如蠕变和氧化。 本研究的目的是表征这两种材料的力学和微观力学的蠕变响应下的多轴等温疲劳和蠕变疲劳响应的这两种结构材料从现有的数据。 将对这两种材料的断裂和失效过程进行广泛的微观结构评估，以开发基于物理的通用寿命预测概念。 一个通用的多轴疲劳寿命预测概念开发的等温情况下，将适用于多轴疲劳寿命数据在这项研究中获得。 ***

9215694 Zamrik A series of multiaxial thermal-mechanical fatigue (TMF) tests are to be conducted using two structural materials: type 316 stainless steel and Nickel-base superalloy Waspaloy. The TMF tests will be conducted in continuous cycling modes and with holds-in- strain/temperature imposed on the continuous cycling waveforms. The hold-periods are imposed in the TMF loading cycles to induce time dependent effects such as creep and oxidation. The objective of this research is to characterize the mechanical and micromechanical TMF responses of these two materials under multiaxial isothermal fatigue and creep-fatigue responses of these two structural materials from available data. Extensive microstructural evaluations of the fracture and failure processes of these two materials will be conducted in order to develop a physical-based universal life prediction concept. A universal multiaxial fatigue life prediction concept developed for the isothermal case will be applied to the multiaxial TMF data obtained in this research study. ***