CN110202158A - 一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修复方法 - Google Patents

一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修复方法 Download PDF

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CN110202158A
CN110202158A CN201910435691.0A CN201910435691A CN110202158A CN 110202158 A CN110202158 A CN 110202158A CN 201910435691 A CN201910435691 A CN 201910435691A CN 110202158 A CN110202158 A CN 110202158A
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integral shroud
rotor blade
monoblock type
longitudinal direction
turbine rotor
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张铀
罗奎林
罗九龙
罗烽月
何勇
陈海生
杨秀恩
王冰雪
张凯
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No 5719 Factory of PLA
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23PMETAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P6/00Restoring or reconditioning objects
    • B23P6/002Repairing turbine components, e.g. moving or stationary blades, rotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/10Formation of a green body
    • B22F10/12Formation of a green body by photopolymerisation, e.g. stereolithography [SLA] or digital light processing [DLP]
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/30Process control
    • B22F10/36Process control of energy beam parameters
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/30Process control
    • B22F10/38Process control to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/50Treatment of workpieces or articles during build-up, e.g. treatments applied to fused layers during build-up
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/60Treatment of workpieces or articles after build-up
    • B22F10/66Treatment of workpieces or articles after build-up by mechanical means
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/06Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
    • B22F7/062Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B33ADDITIVE MANUFACTURING TECHNOLOGY
    • B33YADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00Processes of additive manufacturing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/06Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
    • B22F7/062Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts
    • B22F2007/068Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts repairing articles
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/25Process efficiency

Abstract

本发明公开了一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,包括以下步骤:首先机械打磨叶片,整体去除损伤的叶冠,采用激光修复铸造盖板下的裂纹,将叶尖盖板固定在叶片叶冠上,然后采用整体式激光立体成形技术将叶冠整体成形,并手工加工成形的叶冠面,使其恢复流道型面,最后对修复的涡轮叶片进行无损检测,符合标准后投入使用。本发明采用整体修复的方法,不仅对退化材料去除彻底,而且避免逐一修复的过程,减少工作量,同时,本发明采用通过使用特殊的修复材料,提高了叶冠材料的综合性能。

Description

一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修 复方法
技术领域
本发明涉及航空发动机维修领域,特别是一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修复方法。
背景技术
涡轮工作叶片是航空发动机中的核心零部件之一,在长时间使用过程中承受离心力、热机械交变载荷、高温氧化、热腐蚀等作用。在上述联合作用下叶冠产生了纵向密集损伤,如:叶尖氧化腐蚀减薄、纵向密集裂纹、点腐蚀、以及由密集裂纹和腐蚀联合作用产生的纵向沟槽状开口腐蚀损伤,已经对叶片叶冠造成了较大的结构破坏。上述损伤由于数量多、覆盖面积大、壁厚减薄多,叶冠的几何连续结构破坏、基体材料已退化,现有的修复方法难以实现叶片修复。
发明内容
本发明的目的在于克服现有技术的不足,提供一种航空发动机涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,本发明可广泛应用于无冠及带冠涡轮工作叶片叶冠纵向密集损伤的整体式修复,对叶片叶冠以下区域影响较小,修复区的强度高,周期短,成本低。
本发明的目的是通过以下技术方案来实现的:
一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,包括以下步骤:
S1. 整体去除损伤叶冠,以叶片整体铸造盖板上表面为基准,将基准以上的所有结构全部去除,露出金属光泽平面;
S2. 去除铸造盖板下表面裂纹,将出现裂纹及其附近的表面整块打磨去除,使用激光增材制造技术填补表面;
S3. 固定叶尖盖板,用电阻焊将盖板定位在叶片叶冠上;
S4. 根据叶冠的三维模型设计成形路径,采用激光立体成形技术使叶冠整体成形;
S5. 手工打磨成形后的叶冠,使叶冠恢复流道型面;
S6. 检查叶冠整体,若修复区不存在裂纹或未熔合的材料,将该修复后的转子叶片恢复使用。
步骤S1中,打磨去除方式为数控车床或手工打磨去除。
步骤S2中,激光增材制造技术所用材料为HL180351。
步骤S2中,激光增材制造技术的修复参数为:功率200~400 W,离焦量2~4 mm,送粉量1~3 g/min,扫描速度5~7 mm/S,层高0.2~0.4 mm/层。
步骤S3中,电阻焊所用电压为250~350V,所用电极直径为0.5mm。
步骤S4中,激光立体成形技术所用材料为HL180351。
步骤S4中,激光立体成形技术成形参数为:功率300~500 W,离焦量2~4 mm,送粉量4~6 g/min,扫描速度4~6 mm/S,层高0.6~0.8 mm/层。
步骤S6中,采用荧光探伤或X光探伤检查方式检查叶冠整体。
本发明的有益效果是:
(1)本发明可整体式去除损伤集中的叶冠部位,改变以往叶片缺陷逐一排除方式,降低操作难度,从而根本上取消了叶片待修豁口,避免了众多焊接点导致残余拉应力过大导致裂纹再生,同时,退化材料去除更彻底,保证了叶片材料剩余强度;
(2)整体式激光立体成形叶冠,改变以往逐一修复缺陷的方式,大大降低了纵向密集损伤的修复难度,大幅减少了修复工作量,同时,工艺过程更稳定,利于标准化作业;
(3)三是通过使用特殊的修复材料,提高叶冠材料耐热腐蚀、抗高温氧化、强度塑性等综合性能,改善叶片结构环境强度,降低叶冠使用过程中再次发生损伤的概率;
(4)四是扩大了缺陷修复工艺极限,可以实现铸造盖板以下裂纹修复。
附图说明
图1为高压涡轮工作叶片故障示意图。
图2为去除损伤叶冠后的叶片示意图。
图3为激光修复盖板下裂纹的示意图。
图4为固定叶尖盖板后的叶片示意图。
图5为激光立体成形的叶片示意图。
图6为激光立体成形后的叶片示意图。
图7为恢复流道型面后的叶片示意图。
具体实施方式
下面结合附图进一步详细描述本发明的技术方案,但本发明的保护范围不局限于以下所述。
如图1~7所示,一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,包括以下步骤:
S1. 打磨去除损伤叶冠,以叶片整体铸造盖板上表面为基准,去除基准以上的所有结构,露出金属光泽平面,如图2所示。
步骤S1中,打磨去除方法为数控车床或手工打磨去除。
S2. 去除铸造盖板下的表面裂纹,将出现裂纹及其附近的表面整块打磨去除,如图3所示,使用激光增材制造技术填补表面,修补后的叶冠如图4所示。
步骤S2中,激光增材制造技术所用材料为HL180351,修复参数为:功率200~400 W,离焦量2~4 mm,送粉量1~3 g/min,扫描速度5~7 mm/S,层高0.2~0.4 mm/层。
S3. 固定叶尖盖板,用电阻焊将盖板定位在叶片叶冠上,如图5所示。
步骤S3中,电阻焊所用电压为250~350V,所用电极直径为0.5mm。
S4. 根据叶冠的三维模型设计成形路径,采用激光立体成形技术使叶冠整体成形,如图6所示。
步骤S4中,激光立体成形技术所用材料为HL180351,成形参数为:功率300~500 W,离焦量2~4 mm,送粉量4~6 g/min,扫描速度4~6 mm/S,层高0.6~0.8 mm/层。
S5. 叶冠流道型面恢复,在激光立体成形完毕后采用手工打磨恢复叶冠流道型面,如图7所示。
S6. 无损检测叶冠整体,修复区不允许有裂纹和未熔合,满足要求后放行。
步骤S6中,检查方法为荧光探伤或X光探伤检查。
以上所述仅是本发明的优选实施方式,应当理解本发明并非局限于本文所披露的形式,不应看作是对其他实施例的排除,而可用于各种其他组合、修改和环境,并能够在本文所述构想范围内,通过上述教导或相关领域的技术或知识进行改动。而本领域人员所进行的改动和变化不脱离本发明的精神和范围,则都应在本发明所附权利要求的保护范围内。

Claims (8)

1.一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:包括以下步骤:
S1. 整体去除损伤叶冠,以叶片整体铸造盖板上表面为基准,将基准以上的所有结构全部打磨去除,露出金属光泽平面;
S2. 去除铸造盖板下表面裂纹,将出现裂纹及其附近的表面整块打磨去除,使用激光增材制造技术填补表面;
S3. 固定叶尖盖板,用电阻焊将盖板定位在叶片叶冠上;
S4. 根据叶冠的三维模型设计成形路径,采用激光立体成形技术使叶冠整体成形;
S5. 手工打磨成形后的叶冠,使叶冠恢复流道型面;
S6. 检查叶冠整体,若修复区不存在裂纹或未熔合的材料,将该修复后的转子叶片恢复使用。
2.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征为:步骤S1中,打磨去除方式为数控车床或手工打磨去除。
3.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S2中,激光增材制造技术所用材料为HL180351。
4.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S2中,激光增材制造技术的修复参数为:功率200~400 W,离焦量2~4 mm,送粉量1~3 g/min,扫描速度5~7 mm/S,层高0.2~0.4 mm/层。
5.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S3中,电阻焊所用电压为250~350V,所用电极直径为0.5mm。
6.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S4中,激光立体成形技术所用材料为HL180351。
7.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S4中,激光立体成形技术成形参数为:功率300~500 W,离焦量2~4 mm,送粉量4~6 g/min,扫描速度4~6 mm/S,层高0.6~0.8 mm/层。
8.根据权利要求1所述的一种涡轮转子叶片叶冠纵向密集损伤的整体式修复方法,其特征在于:步骤S6中,采用荧光探伤或X光探伤检查方式检查整体叶冠。
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CN112276082A (zh) * 2020-10-15 2021-01-29 中国人民解放军第五七一九工厂 航空发动机压气转子叶片叶尖三维尺寸修复方法
CN112427637A (zh) * 2020-11-20 2021-03-02 中国人民解放军第五七一九工厂 定向凝固晶涡轮叶片叶尖深裂纹的修复材料及修复方法
CN113441725A (zh) * 2020-03-27 2021-09-28 斗山重工业建设有限公司 利用增材制造的涡轮机叶片的修复方法
WO2022179205A1 (zh) * 2021-02-26 2022-09-01 中国航发上海商用航空发动机制造有限责任公司 超薄结构增材制造修复的方法

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