DD499单晶合金持久性能薄壁效应  

Influence of Thin Wall on the Stress Rupture Properties of DD499 Single Crystal Superalloy

作　　者：余昌奎[1,2] 于金江[1] 仉凤江 石峰[1] 孙晓峰[1] 

机构地区：[1]中国科学院金属研究所,辽宁沈阳110016 [2]贵州黎阳航空动力有限公司,贵州平坝561114

出　　处：《铸造》2014年第5期479-483,共5页Foundry

基　　金：国家基础研究项目(2010CB631200;2010CB631206);国家自然科学基金(50931004;51001103)

摘　　要：研究了试样壁厚对DD499单晶高温合金持久性能及其断裂特性的影响。在760℃/790MPa和1040℃/165MPa条件下,壁厚为0.8 mm和1.2 mm试样的持久寿命明显低于标准试样,表现出显著的薄壁效应,壁厚和持久塑性间没有明显的函数关系。在760℃/790 MPa条件下,0.8 mm厚度的试样主要以滑移开裂为主,随着壁厚的增加,解理断裂转向混合断裂,延性断裂因素增加。1 040℃/165 MPa条件,断裂特性相似,但壁厚为0.8 mm和1.2 mm试样断口表面存在着较厚的氧化层,其有效截面显著减少。Influence of thin wall on stress rupture properties and the fracture character of DD499 single crystal superalloy were investigated. Under the condition of 760 ℃/790 MPa and 1040 ℃/165 MPa, stress rupture life of the samples with 0.8 mm or 1.2 mm thickness is significantly less than that of the standard sample, which exhibits thin wall effect. There is an ambiguous function relationship between thickness and stress rupture ductility. At 760 ℃ and 790 MPa, slip crack is the main fracture character of the specimen with 0.8 ram. The cleavage fracture turn to mixture fracture with the increase of wall thickness, the tensility fracture factor is increasing. At 1 040 ℃ and 165 MPa, the fracture surface with 0.8 mm or 1.2 mm thickness possesses relative thick oxidation layer though all test specimens represent similar cavity accumulation failure character, it induces that effective section evidently decreases.

关 键 词：单晶合金 持久性能 薄壁效应 

分 类 号：TG132.3[一般工业技术—材料科学与工程]