热处理态Ni-Cr-Al合金的拉伸性能及微观变形机理  

Tensile properties and microscopic deformation mechanism of heat treated Ni-Cr-Al alloy

作　　者：马李 何录菊 莫才颂 盘茂森 Ma Li;He Luju;Mo Caisong;Pan Maosen(College of Mechanical and Electrical Engineering,Guangdong University of Petrochemical Technology,Maoming Guangdong 525000,China)

机构地区：[1]广东石油化工学院机电工程学院,广东茂名525000

出　　处：《金属热处理》2019年第5期47-51,共5页Heat Treatment of Metals

基　　金：广东省自然科学基金(2017A030307018);广东省橡塑材料制备与加工工程技术研究中心开放课题(2015B090903083);广东省扬帆计划项目(201533018)

摘　　要：采用电子束气相沉积方法制备了Ni-Cr-Al合金,对试样进行了固溶及时效处理,考察了20～1000℃不同温度下合金的拉伸性能及位错结构特征。结果表明,随着试验温度升高,合金拉伸强度逐渐降低,断口形态大多为韧窝和准解理断裂构成。室温下,当合金中的γ'粒子达到临界尺寸后,位错弯曲绕过γ'粒子; 400℃时,位错密度增加,缺陷界面形成外禀层错,而反相畴界的存在会使位错切过γ'粒子的阻力增大; 700℃时,位错能够沿着基体弯曲移动,并产生攀移和交滑移; 1000℃时,位错线变长并发生弯曲,最终形成包围γ'粒子的位错环。Ni-Cr-Al alloy was prepared by electron beam vapor deposition,further solution treated and aged,then its tensile behaviors and dislocation configuration characteristics under different temperatures in range of 20-1000 ℃ were investigated.The experimental results indicate that as the temperature increases,the tensile strength of the alloy decreases gradually,and the fracture morphology becomes mostly dimpled and quasi-cleavage fracture.At room temperature,when the γ’ particles in the alloy reach the critical size,the dislocation bending bypasses the γ’ particles.At 400 ℃,the dislocation density increases and the defect interface forms an external stacking fault,while the existence of an antiphase domain boundary increases the resistance of dislocation cutting through γ’ particles.At 700 ℃,dislocations can bend and move along the matrix,resulting in climbing and cross-slip.At 1000 ℃,the dislocation lines become longer and bend,resulting in the formation of dislocation rings surrounding γ’ particles.

关 键 词：NI-CR-AL 高温合金 电子束气相沉积 时效 力学性能 断口 位错 

分 类 号：TG146.15[一般工业技术—材料科学与工程]