关键词：高温合金GH4169G；车削-喷丸复合加工；服役环境;表面完整性演化中图分类号：V216.8DOI：10.3969/j.issn.1004-132X.2025.04.015 开放科学（资源服务）标识码（OSID）：

Evolution Mechanism of Surface Integrity of GH4169G Turning-shot Peening under Thermal and Mechanical Loads

HE Zhe1LI Jiale1SHI Kaining1FAN Yuchang³HUANG Xinchun²* 1.Key Laboratory of High Performance Manufacturing for Aero Engine（Ministry of Industry and Information Technology），Northwestern Polytechnical University，Xi'an，710072 2.Office of Science and Technology，Northwestern Polytechnical University，Xi'an，710072 3.Zhijian Laboratory，Rocket Force University of Engineering，Xi'an，710025

Abstract： A study of the evolution mechanism of surface integrity of turning-shot peening composite machining under service load conditions was carried out for the nickel-based superalloys GH4169G for aero-engines. The forms of thermal，mechanical，and thermo-mechanical loads on surface integrity were analyzed by simulating thermo-mechanical load tests under service environments. The thermo-mechanical loading model for surface integrity control and the residual stress and microhardness evolution model with cosine function control factor were established. The laws of residual stress relaxation under thermo-mechanical loading and the laws of microhardness changes and surface microstructure changes were mastered. The results provide basic data for mastering the evolution of surface integrity of nickel-based superalloys processed under service environments. The surface integrity control processes were further optimized.

Key words： superalloy GH4169G；combined turning and shot peening；service environment； evolution of surface integrity

0 引言

GH4169是一种沉淀强化镍基高温合金，在650°C 下的屈服强度居变形高温合金首位，具有良好的高温抗辐射、抗氧化和抗腐蚀性，以及较高的高温疲劳强度和断裂塑性及韧性[1-2]。GH4169G是在GH4169合金成分基础上采用B、P微合金强化后发展而成的一种新型合金[3]，其高温持久性能和抗蠕变性能较GH4169有进一步提高，被应用于新一代航空发动机整体叶盘等关键构件的研制中[4]。整体叶盘制造过程中，车削加工起“控形”的作用，喷丸强化起“控性”的作用，其加工品质直接决定了构件的工作性能与疲劳性能。在服役过程中，由于受到热载荷和机械载荷的综合影响，构件的表面完整性特征不断变化，常会出现残余压应力场松弛、显微硬度下降、组织结构变化等现象[5-7]，削弱了喷丸工艺对构件的“强化”效果，从而导致构件的服役寿命下降。

因此，研究构件在服役环境下的表面完整性特征演化规律是实现表面完整性控制、疲劳性能提高的关键。

目前，已有学者对高温合金、钛合金等难加工材料在服役条件下的表面完整性变化规律开展了研究。CAI等[8]在研究高温合金 In718 喷丸残余应力的高温松弛规律时发现，喷丸后的残余应力松弛规律符合Zener-Wert-Avrami（ZWA）模型。FOSS等9在研究高温环境下高温合金RR1000的残余应力松弛过程中观察到在 700^∘C 时残余应力大幅降低。WU等[10]研究了热载荷作用下高温合金 In625 喷丸残余应力和显微硬度，随着环境温度的升高，两者的下降速度都越来越明显。……