H13和45鋼空蝕性能及空蝕機(jī)理的研究.pdf

1、江蘇大學(xué)碩士學(xué)位論文H13和45鋼空蝕性能及空蝕機(jī)理的研究姓名：馮暖申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：材料學(xué)指導(dǎo)教師：王樹奇201206江蘇大學(xué)碩士學(xué)位論文ABSTRACTCavitationerosionisacomplicatedphenomenonofdestroymentonthesolidsurfaceUntilnowresercherscannotestablishtheperfectmechanismforitTheH13and45

2、steelweretakedasexperimentalmaterialinthisstudyTheinfluenceofmicrostructureoncavitationpropetieswasinvestigatedbymass—lossmethodThecavitationmechanismofthistwosteelswereexploredbyexaminingevaluatingandanalysisthemorpholo

3、gyofthewornsurfacesandsectionsurfacesTheexperimentalresultsshowthatthecavitationresistanceofH13steelwithvarioustemperedmicrostructureswasbetterthan45steel，thisisduetotheappreciablesolidsolutionstrengtheningofthealloyinge

4、lementsintheH13steelThespecimensofH13steeltemperedat200℃and500℃presentedthebetterwearresistanceamongallthetemperedspecimensByprespheroidizingannealing，thecavitationresistanceoftemperedmicrostmcturesofH13steelWasimprovedT

5、hisisbecauseofthestructureuniformityandthehighercapabilityofplasticdeformationThecavitationmechanismWasalowcyclefatiguefailure麗mmorefatiguesourcesThemicrostructureshaveasignificantimpactoncavitationcapabilityofmetalmater

6、ialsWiththeincreasingofthetemperedtemperaturesandtheprecipitationofcarbidesinH13steel，thesurfacesofspecimensgraduallyshowedthemorphologyofdimplefracturesForthespheroidizingannealingspecimens，thestyleoffracturingonthesurf

7、aceWasquasi—cleavagefractureDuetothelowstrengthandtoughness，thetemperedspecimensof45steelexperiencedsevereplasticdeformationintheinductionperiodofcavitationandgeneratedsomemicroscopicpitsatthedefectsofdeformationUnderthe

8、hi：ghstresses，thepitslinkedwitheachotherandextendedtobiggersizeThecavitationresistanceoftemperedspecimensfor45steeldecreasedwithelevatorytemperedtemperaturesKeywords：cavitationmechanism；microstmcture；lowcyclefatigue；cavi