简介:采用金相显微分析和电镜及能谱分析方法对延伸率不合格的Q235B热轧普板进行非金属夹杂物、金相组织分析。分析结果认为Q235B热轧普板延伸率不合格是由于钢板中心存在大量的条带状MnS夹杂所致。并根据分析结果,提出提高冶炼质量,控制钢水中的硫和杂质元素的含量,对提高延伸性能十分重要的观点。
简介:ThemicrostructuralchangesofFe83Si4B13amorphousmotheralloyduringtheheatingprocesswereinvestigatedbyLaserScanningConfocalMicroscopy(LSCM),andthephasetransformationwasdeterminedbytheThermo-Calccalculations.ThedifferencesinthemeltingpointsmeasuredbyDifferentialScanningCalorimetry(DSC)andLSCM,andthoseobtainedbyThermo-Calccalculationswerealsodiscussed.ItisfoundthatthemeltingpointsmeasuredbyDSCandLSCMarerelativelysimilar,whereastheonsetandendofthemeltingtemperaturescalculatedbyThermo-CalcsoftwarearehigherthanthosemeasuredbyDSCandobservedbyLSCM.
简介:Themicrostructuresandprecipitatesinbasemetalsandheataffectedzones(HAZs)oftwoZr-Bmicroalloyedsteelswerecharacterizedbymeansofopticalmicroscopy(OM),transmissionelectronmicroscopy(TEM)andenergydispersivespectrum(EDS).Ithasbeenfoundthatprecipitatesoftensofnanometersinsizearepresentinthebasemetalsofbothsteels.Theaverageparticlesize,however,intheZr-BsteelwithTiislargerthanthatinthesteelwithoutTi.Afterthermalsimulations,inbothcases,theMnSsulfidescannucleateoncubic(Nb,Ti)(C,N)carbonitridesandnearlysphericalZr-bearingcompounds.TheprecipitatesintheHAZsofbothsteelsarecoarserthanthoseinthebasemetals,intherangesof150-200nmand50-100nmforTiaddedandTi-freesteels,respectively.