ADVANCED MATERIALS · AEROSPACE MANUFACTURING

Advanced
Materials

High-Precision Thermomechanical Processing of TC4 Titanium Alloy for Aerospace Components

面向航空发动机大型复杂钛合金构件的高精度成形与性能调控研究

TC4 TitaniumThermomechanical ProcessingMicrostructure Control

AEROSPACE ENGINE · CASING RING高精度钛合金航空发动机机匣环

01 / CONTEXT

Aerospace Materials Challenge

航空先进材料制造挑战

Aero-engine casings are critical load-bearing, containment, and connection structures. Their manufacturing accuracy directly affects engine assembly and in-service reliability.航空发动机机匣是承载、包容与连接发动机核心系统的关键结构件，其制造精度直接影响整机装配与服役可靠性。

Large Scale · 大尺寸Thin Wall · 薄壁结构Complex Surface · 复杂曲面High Precision · 高尺寸精度

In the conventional route of ring rolling, heat treatment, and extensive machining, distortion and residual stress remain difficult to control simultaneously.传统“环轧成形—热处理—大量机加工”流程中，热处理变形与残余应力难以协同控制。

01Severe Heat-Treatment Distortion热处理变形严重

02Nonuniform Residual Stress残余应力分布不均

03Excessive Ovality椭圆度较大

04Large Machining Allowance加工余量大

05Low Material Utilization材料利用率低

传统航空发动机机匣制造流程图 — CONVENTIONAL ROUTE传统制造流程

02 / OBJECTIVE

Research Objective

研究目标

PROPOSED STRATEGY

Multiple Circumferential Hot Expansion + 650℃ / 3h Annealing“多次环向热胀形 + 650℃/3h 退火”的形变热处理一体化制造工艺

Dimensional Accuracy

高精度尺寸控制

Residual Stress

残余应力降低

Microstructure

微观组织优化

Strength & Ductility

强塑性能匹配

CONVENTIONAL

Ring Rolling · 环轧↓Heat Treatment · 热处理↓Machining · 机加工

INTEGRATED PROCESS

Ring Rolling · 环轧↓Multiple Hot Expansion · 多次环向热胀形↓650℃ / 3h Annealing · 退火↓High-Precision TC4 Casing Ring · 高精度机匣环件

03 / INNOVATION

Innovative Processing Strategy

核心技术创新

Multiple Circumferential Hot Expansion

多次环向热胀形技术

Circumferential deformation uniformity is improved by coordinating expansion cycles, ring rotation angles, and deformation allocation, thereby minimizing final ovality.通过协同控制胀形次数、环件转动角度与单次胀形量分配，改善环件周向变形均匀性，显著降低最终椭圆度。

Expansion Cycles
Rotation Angle
Deformation Allocation

胀形过程中环件多角度转动方案示意图 — RING ROTATION环件转动示意图

不同环件转动次数的有限元模拟结果 — FINITE ELEMENT有限元模拟结果图

Temperature-Dependent Finite Element Modeling

基于温度变化的有限元模拟

Cyclic loading–unloading tensile tests reveal the evolution of TC4 elastic modulus. Incorporating this behavior into the finite element model improves prediction accuracy.通过循环加载—卸载拉伸实验获得 TC4 钛合金杨氏模量变化规律，并输入有限元模型，提高预测精度。

Temperature ↑Loading Cycles ↑Strain ↑Elastic Modulus ↓

不同温度下 TC4 钛合金杨氏模量随应变变化曲线 — MODULUS CURVE杨氏模量变化曲线

04 / MATERIAL SCIENCE

Microstructure & Mechanical Performance Optimization

组织调控与性能优化

Microstructural evolution was investigated from 500℃ to 800℃. Increasing temperature raises the β-phase fraction, reduces deformation resistance, and improves high-temperature plasticity; excessive temperature, however, coarsens secondary α phase and reduces structural stability.在 500℃—800℃ 范围内研究组织演变。随温度升高，β 相含量增加、变形抗力降低、高温塑性提高；但过高温度会引起次生 α 相粗化与组织稳定性下降。

OPTIMUM WINDOW650℃ / 3hAnnealing Treatment