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1、摘要壓電材料有著廣泛的應(yīng)用前景,尤其是在智能元件中有著廣泛的應(yīng)用。含裂紋、圓孔、-I嘲@L等各類缺陷的壓電材$:tfi9動力學(xué)問題一直是國內(nèi)外力學(xué)界和材料學(xué)界研究的熱點,然而刈‘于復(fù)合型缺陷的研究較為少見。本文研究雙棚瓜咆材料吖1界面二1}:圓孔邊裂紋復(fù)合型缺陷的動力反平面行為,其r_}Ijj要研究界面非圓孔的加入對界l面裂紋尖端動應(yīng)力強度因f的影響,目的是對]:程設(shè)計提供一一定的理淪基礎(chǔ)。首先,利』f]保教映射法構(gòu)造出具有非圓孔型凹陷半無限壓電介質(zhì)的Green函數(shù),得到?jīng)]有裂紋情況卜單位線載荷入射壓電材料產(chǎn)生的位移場和電位勢場。然后,采用“切割
2、”和“契合”的方法構(gòu)造非圓孔邊裂紋復(fù)合型缺陷,并利用本文的Green函數(shù)和界面應(yīng)力與位移的連續(xù)性條件,建一、Z第一類Fredholm定解積分方程,利胍卣接數(shù)值積分解法,得到孔邊動應(yīng)/J強度斟予的解析表達(dá)式。最后,為了證f
3、』]本文力‘法的lF_確性i,部分算例與已有川關(guān)文獻(xiàn)進(jìn)行對比,得出誤差范圍在允許范圍內(nèi),即可證明本文方法的iF確性。作為算例,給小了缺陷在不同幾何參數(shù)、不同壓t包特征參數(shù)、1i同波數(shù)情況]、.,對裂紋尖端j動應(yīng)力強度?了的s?,,".5llln’J,汁算結(jié)果以圖的形式給出。關(guān)鍵詞:雙相壓IIxH‘料;保角映射;z力力反ihⅢj二
4、為;Greeni:均數(shù);鄉(xiāng)1Ⅲj㈦到孔邊裂紋;動應(yīng)力強度因了ABSTRACTThepiezoelectricmaterialhasbeenwidelyusedinthenewintelligentmaterials.Dynamicsofthepiezoelectricmaterialwithallkindsofdefects.suchascracks,holes.non—circularcavityhavebeenahottopicinmechanicsandmaterialshomeandabroad.butthepapersaboutcomp
5、lexdefectsarefew.DynamicantiplanebehaviorsoftheradialcracksattheedgeoftheuncircularcavityaresolvedinpiezoelectricmediumandpiezoelectricbjmaterjalsTheinfluenceproducedbythejoinoftheuncircularcavityismainlyresearchedinthepaper,inordertoprovidesometheoreticalbasisforengineeringd
6、esign.Firstofall,basedonthemethodofconformalmapping,thedisplacementGreenfunctionsandtheelectricpotentialGreenfunctionwhicharesuitableforthepresentproblemareconstructedthecrack.divisiontechnique.Thecompounddefectoftheuncircularcavitywithinterfacecrackisconstructedaccordingtoth
7、econjunctionmethod.BasedonGreen‘Sfunctionswhichareagreedwitht11eboundaryconditions,apairofthefirstkindofFredholmintegralequationsforsolutionscanbeestablished.Andtheintegralequationsaresolvedbythedirectnumericalintegrationmethod.AtthesametimedynamicstressintensityIhctor(DSlF)w
8、illbesolved.Andthen,someexamplesandtherelatedliteraturewerecomparedinordertoprovethecorrectnessofthismethod.Therangeoferrorshouldbewithintheallowablerange.Finallyr.thenumericalresultsrevealtheeffectsofthelengthofthecrack,theuncircularcavity,'radius,theincidentwavefrequencyand
9、thematerialparametersondynamicstressintensityfactorsofthecrack—tip.I