激光清洗技术是利用高能密度激光束辐照物体表面,使表面污染层产生振动、烧蚀、蒸发甚至气化等物理化学反应,直至脱离物体表面,达到清洗目的,它不会损坏物体本身,可提高航空发动机金属零件的维修质量.

整体叶盘叶片的服役损伤可采用熔焊、高能束增材制造、线性摩擦焊等技术进行修复.为避免热处理影响整体叶盘未修复区域的组织性能以及产生变形,一般在修复区域采用局部热处理来消除焊接应力和调整组织性能.本文综述了局部热处理的技术原理、系统组成、评定准则和模拟仿真,介绍了整体叶盘叶片损伤修复局部热处理技术的研究进展,分析了不同局部热处理技术面临的挑战和需要解决的应用基础问题.

通过对Nadcap审核要求的学习,分析了真空钎焊审核前的准备工作,主要包括标准及审核清单清查、内审报告、"人机料法环测"等,为相关领域取得Nadcap认证提供参考.

整体叶盘是先进高性能航空发动机中实现结构创新与技术跨越的核心部件,是衡量航空发动机先进性的重要标志.整体叶盘在制造和工作过程中往往因单个叶片加工尺寸超差或外物打伤而报废停用.如果对叶片损伤的整体叶盘换用新品,将大大提高发动机制造和维修成本.本文综述了压气机整体叶盘叶片损伤修复技术现状、修复技术路线设计和修复关键技术的研究进展,并分析了修复技术需要解决的基础问题.

The numerical simulation of three dimensional free bending process of copper complex axis hollow component was investigated by using the finite element analysis method based on ABAQUS software.The effects of the key process parameters including the offset between tube axis and bend die axis (u),the distance between the center of the bending die and the head of guide sleeve (M) and the Z axial push velocity (v) on the forming quality of the 3D tubular bending components were studied respectively.In addition,the stress and strain states of the forming zone were analyzed and the optimal 3D free bending forming process parameters of the complex bending component were obtained.Finally,the free bending test of copper tube was carried out based on the optimal simulation results.The results indicate that the dimensions of the bending components are similar to the simulation results and close to the design size under the forming condition with u value of 0.25 mm,M value of 26.5 mm and v value of 20 mm · s-1.There are no obvious cross section distortion,excessive thickening and thinning of wall thickness.The formed components have good quality and the simulation results provide a technique reference for the forming of the copper complex axis hollow component.

数值模拟技术的出现使单晶涡轮叶片激光增材工艺的开发成本显著降低.本文简要介绍了数值模拟单晶涡轮叶片激光增材过程的基本原理以及存在的问题,为其广泛应用奠定基础.

钎焊是高温合金零部件修理的重要工艺。采用科学合理的钎焊前处理技术，特别是清洗技术，是获得高质量钎焊接头的前提和保证。本文针对高温合金钎焊的特点和对零件表面清洁度的要求，综述了高温合金钎焊前处理技术的研究现状，着重介绍了化学清洗、盐浴清洗、氢还原处理、真空清洗、高压水清洗、激光清洗、热离子清洗和机械打磨处理等钎焊前处理技术，展望了高温合金钎焊前处理技术的研究方向。

To repair TC4 titanium stator blades of large aero-engine fan casing,the repair process of damaged blades by laser cladding was researched,and the compositions,microstructure,microhardness and mechanical properties of the laser cladding zone were analyzed.The experimental results indicate that contents of elements such as O,N,H in the laser cladding zone comply with the standard requirements.The laser cladding zone consists of columnar grain with typical Widmanstatten structure in which fine martensite structure is distributed.The heat affected zone consists of the mixture structure of columnar grain and duplex microstructure,transiting from mixture structure to duplex microstructure as getting close to the base metal.The average microhardness of the laser cladding zone is 15% higher than that of the base metal,and the microhardness transition from the laser cladding zone to the metal base is mild.The tensile strengths by room-temperature tensile test,elevated temperature tensile test(at 400 ℃)and thermal exposure test for laser cladding TC4 titanium sample are all higher than those for the base metal,while the elongations are slightly lower.The damaged stator blades are repaired by single-path and multi-layer laser cladding method.The fan casing is put into use after acceptance.

针对某型发动机高压涡轮工作叶片内腔网状冷却孔中堵塞的异物,研究了一种嵌入接触式微孔清理技术,采用专用清洗剂,并设计了专用清理工具,形成了高压涡轮工作叶片组合清理工艺.经该技术清理后的高压涡轮工作叶片,可获得80%以上的内腔清洁度合格率.

简述了3D打印技术在解决航空发动维修的零备件采购、提升再制造能力、战场应急抢修中发挥的重要的作用,具体分析了航空发动机零部件3D打印技术体系及其在高压涡轮叶片维修中的应用.

Turbine blades which work permanently under very serious conditions is one of the key parts of aero -engines.Microstructure and properties of turbine blades will be degraded after a certain period of service .The service life of turbine blades can be greatly prolonged if their microstructure and properties are rejuvenated timely .Main technical route of regenerating microstructure and properties of turbine blades by heat-treatment were briefly discussed .

利用ANSYS软件对某型APU涡轮导向叶片起动-停车循环中不同时刻的温度场和应力/应变场分布进行计算分析,确定了叶片上失效危险点的位置、危险点的应变随温度变化的过程以及危险点的周期应力/应变范围,为后续修复技术设计和寿命预测奠定了基础.

High performance thermal barrier coating was composed of bond coat NiCrAlY and top coat nanostructural zirconia.NiCrAlY coating was fabricated by high velocity oxygen fuel spraying,while nanostructural zirconia coating was fabricated by atmosphere plasma spraying.Both processes were optimized by means of orthogonal design.The morphology and property of the thermal barrier coating prepared by these optimal processes were analyzed.The results indicate that the porosities of NiCrAlY bond coat and nanostructural zirconia top coat are less than 2% and about 15%,respectively.The tensile samples are bonded using solid membrane adhesive.The bond strength value of the sample measured by tensile adhesion test is about 30.4 MPa.The thermal shock test is performed by water quenching method.The sample is heated in furnace at 1100 ℃ and then quenched into ambient water.The thermally grown oxide of thermal barrier coating after 50 cycles is compact Al2O3.