第26卷第7期2011年7月

文章编号:1000-8055(2011)07-1551-06

航空动力学报

JournalofAerospacePower

Vol.26No.7

Jul.2011

激光冲击强化提高压气机叶片疲劳性能研究

何卫锋,李应红,李 伟,李玉琴,李启鹏

(空军工程大学工程学院,西安710038)

摘 要:根据1Cr11Ni2W2MoV不锈钢材料性能,确定了激光冲击强化参数;并通过标准试片疲劳试验,验证了该参数条件下激光冲击强化提高不锈钢材料振动疲劳寿命的有效性.设计了不锈钢叶片振动疲劳试验,确定了叶片冲击强化部位和方式,对强化叶片进行了型面检查、一阶弯曲振动疲劳试验和强化机理研究.结果表明:激光冲击强化后的叶片各个截面尺寸在设计范围之内,强化后叶片的应力-循环次数(S-N)曲线往上移动,提高了叶片的疲劳强度,在660MPa应力水平下,叶片的振动中值疲劳寿命提高70%;激光冲击强化引起的残余应力和表层微观组织变化是疲劳强度提高的主要原因.关 键 词:激光冲击强化;压气机叶片;振动;疲劳寿命;残余应力中图分类号:TG665;V216.3 文献标志码:A

Lasershockpeeningonvibrationfatiguebehaviorofcompressorblade

HEWe-ifeng,LIYing-hong,LIWei,LIYu-qin,LIQ-ipeng

(TheEngineeringInstitute,

AirForceEngineeringUniversity,Xi an710038,China)

Abstract:Accordingtothemechanicalperformanceofthe1Cr11Ni2W2MoVstainlesssteel,thetechnicalparametersoflasershockpeening(LSP)weredetermined.Thestandardcouponswith/withoutLSPweretestedforexaminingthefatigueperformance.ItprovesthatLSP,withtheselectedparameters,canimprovethestainlesssteel'svibrationfatiguelifere-markably.Fromtheexperimentresultsofcoupons,thevibrationfatigueexperimentforthecompressorbladeinonecertainaero-enginewasdesignedaccordingtothestructureandloadsoftheblade.Thetreatedzonewasdesignedonthesurfacewherethevibrationstressisthemostsevere.Inordertoavoidmacroscopicaldeformation,thebladesweretreatedonbothsidessimultaneously.ThisconfirmsthatdifferentsectionparametersafterLSPonthebladearewithintherangeofdesignrequests.ThevibrationfatigueresultsindicatethattheS-N(stress-numberofcycles)curvewithLSPmovesupascomparedwiththatonewithoutLSP.Whenthemaxvibratorystresswasabout660MPa,thebladefatiguelifewithLSPwaspro-longedfor70%.Finally,thereasonswereanalyzedfromtheresidualcompressivestressandmicrostructureafterLSP.

Keywords:

lasershockpeening;compressorblade;vibration;fatiguelife;residualstress

能量并发生爆炸性气化蒸发,产生高压(>1GPa)的等离子体冲击波,利用冲击波的力效应使表层材料微观组织发生变化,在较深的厚度上残留压

激光冲击强化(LSP)采用短脉冲(几十纳秒)的高峰值功率密度(>10W/cm)的激光辐照金属表面,使金属表面涂覆的吸收保护层吸收激光

收稿日期:2010-05-13;修订日期:2010-11-11

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作者简介:何卫锋(1977-),男,湖南桃江人,讲师,博士,主要从事激光冲击强化技术研究.