一种含Re镍基合金在高温时效期间的组织演化  

Microstructure Evolution of a Nickle-Based Superalloy Contain Re during Aging

作　　者：李唐[1] 田素贵[1] 夏丹[1] 王明罡[1] 于兴福[1] 

机构地区：[1]沈阳工业大学,辽宁沈阳110023

出　　处：《稀有金属材料与工程》2008年第11期1924-1929,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金项目(50571070);辽宁省教育厅基金项目(2004C004)资助

摘　　要：通过对一种含Re镍基合金进行1100℃长期时效处理及组织形貌观察,研究了时效处理对含Re镍基合金组织结构的影响。结果表明:元素W、Re可促进TCP相的析出,合金在1100℃长期时效期间,TCP相沿{111}晶面<110>方向以共格方式析出,在不同晶面多组针状TCP相可相互垂直、或互成60o角排列,并确定出析出的TCP相为μ相。在μ相析出的初始阶段,由于两相共格界面应变能的作用,使μ相沿γ′相的{111}晶面呈薄片状析出。随高温时效的时间延长,片状μ相增厚,两相界面失去共格,使晶格应变能降低;随后按界面能最小原理,μ相局部区域出现沟槽,可提高元素Re、W的化学位,其μ相不同区域的化学位之差促使元素扩散及μ相逐渐熔断,并直至发生球化,其中,两凸起μ相之间的界面张力σμ/μ是使μ相沟槽不断溶解加深及发生球化的驱动力。By means of the aged treated for longer time at 1100 ℃ and microstructure observation, an investigation has been made into the influence of the aged time on the microstructure of a nickle-based superalloy. Results show that the elements W and Re may promote the precipitation of TCP phase. After aged for long time at 1100 ℃, the TCP phase is precipitated in the form of the coherent lattice along the { 111 } planes and 〈110〉 orientation, which is determined as μ phase by means of the electric diffraction analysis. In the initial stages of μ phase precipitated, the μ phase is precipitated in the form of the sheep-like structure due to the role of the coherent lattice strain energy. The observed strip-like μ phase may be arranged in the upright each other or 60° each other on the different crystal planes, and the width plane in the strip-like μ phase is parallel to the { 111 } planes of y phase. The thickness of the strip-like g phase may be increased as the aged time is prolonged, which decreases the lattice strain energy of μ/γ phases interfaces due to the loss of the coherent interfaces. Whereafter, the groove appears in the local regions of the strip-like μ phase according to the principle of the interfaces energy minimum, which enhances the chemical potential energy of the elements W and Re. In the future, the difference of the chemical potential energy in the different regions of the strip-like μ phase promotes the diffusion of the elements W, Re and the dissolving abruption of the location region of μ phase, and up to the spheroidized of μ phase occurs. Thereinto, the interfaces tension σμ/μ between the protuberant μ phase is thought to be the driving force of the groove dissolved and spheroidized of μ phase.

关 键 词：镍基合金 高温时效 TCP相 球化 驱动力 RE 

分 类 号：TG156.92[金属学及工艺—热处理]