高温环境下应力变化与金属氧化行为的耦合模型  

Analytical Modeling on the Stress Evolution and Oxidation Process of Metals in a High Temperature

作　　者：王颖[1] 张洋[2] 张显程[2] 

机构地区：[1]江苏省特种设备安全监督检验研究院,南京210036 [2]华东理工大学承压系统与安全教育部重点实验室,上海200237

出　　处：《机械工程学报》2015年第12期36-42,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金重点资助项目(51175177;51322510;51371082)

摘　　要：生长应力伴随氧化行为的进行而产生。同时,生长应力的存在对氧化膜的生长速率及表面完整性都有着显著的作用。尤其在外部载荷作用下,应力状态及氧化行为的分析变得更为复杂。基于CLARKE生长应变理论,一种高温加载环境下应力变化与氧化行为的耦合模型被提出,外加载荷、弹性应变、生长应变、蠕变应变及氧化膜厚度之间的复杂关系被予以澄清,实现了对氧化速率、应力状态的准确预测。通过模拟计算,表征应力的变化规律及其对氧化行为的影响。无载荷时,生长应力不断累积,当生长应变和蠕变应变的速率相同时,生长应力增长至最大值,随后逐渐降低。外加应力的引入改变了氧化膜内的应力状态,外加拉应力和压应力分别对氧化膜的生长起到了促进和抑制的作用。Growth stress is generated during oxide scale growth process. At the same time, the growth process and integrity of oxide scale are significantly affected by the existence of growth stress. Particularly when mechanical loads are applied to the oxide/metal system, the situation becomes more complicated. Based on CLARKE＇s growth strain theory, a comprehensive analytical model is presented to predict the stress evolution and oxidation process of metals in a high temperature environment. The interaction among applied mechanical loads, elastic strain, growth strain, creep strain and scale thickness is clarified. The predicted result is accurate and reliable. Without any applied loads, growth stress is accumulated along with time. The maximum stress is reached where deforming rate of growth strain and creep strain are equal. After that, growth stress is drawn down gradually. Oxide stress is influenced by the mechanical loads. The scale growth rate is promoted by tensile loads while retarded by compressive loads.

关 键 词：模型 氧化 应力 蠕变 

分 类 号：TG151[金属学及工艺—热处理]