简介：摘要通过制定4140钢种成分﹑工艺路线﹑生产过程中工艺参数进行组织生产，获得了较为理想的板材性能数据，板材的外形质量未发生因应力不均而造成的瓢曲现象．

简介：GlowdischargeplasmanitridingofAISI304austeniticstainlesssteelhasbeencar-riedoutfordifferentprocessingtimeunderoptimumdischargeconditionsestablishedbyspectro-scopicanalysis.ThetreatedsampleswereanalysedbyX-raydiffraction(XRD)toexplorethechangesinducedinthecrystallographicstructure.TheXRDpatternconfirmedtheformationofanexpandedaustenitephase(γN)owingtoincorporationofnitrogenasaninterstitialsolidsolu-tionintheironlattice.AVickersmicrohardnesstesterwasusedtoevaluatethesurfacehardnessasafunctionofindentationdepth(μm).Theresultsshowedclearevidenceofsurfacechangeswithsubstantialincreaseinsurfacehardness.

简介：【摘要】为了提高产品检验质量，本文针对AISI 4145HMOD进行探伤，低倍断口等试验，分析问题产生的真正原因，为今后改善产品质量，提供了重要参考数据。

简介：TheSteelAISI4145HMforseniorpetroleumdrillofBXSteelwasproducedbythefollowsheet:hotmetalpretreatment→converter→LF→RH→caster350mm×470mmrectangularbillet→hotdelivery→reheating→800millrolling→insulation→straightening→anneal→grinding→inspection→packagingandpayintotreasury→shipment.SelectedBXSteelparticularhormetal,adoptedhotmetaldesulphurizationpretreatmenttechnology.TheLFrefiningmakingthewhiteslag,andkeepacertaintime.TheRHtreatmentmustmakesurethevacuumdegreeandrefiningtime,moreimportantlycontrollingargonblowingprocess.Inaddition,mustdesignpropertechnologydatacontinuouscastingsimilarsuperheat,castingspeed,andspecificwaterflowrate.Dependontechnologicalmeasures,theproductbeenhadseriesofthequalities:homogeneityofchemicalcomposition,lowcontentofharmfulelements,highpurity,compactorganization.Adoptedtheprocessofcastingbillethotdeliveryandhotcharging,usedsteppingheatingfurnace,anddesigningreasonablethermalparameters.Two-highreversingmillroughrollspreparationsquarebillet,short-stress-pathrollingmillrollsroundbar.Steelproductsbadholdingandcontrollingsoakingtimeandtemperature.Steelproductsbadannealed,andannealingprocessmustbeencontrolledforensuringsteelhardnessuniform.Foravoidingresidualstress,steelbeenstraightenedbeforeanneal.Thetestresultsandusingeffectshowsthattheproducingwithuniformannealinghardnessandniceprocessingproperties,niceoverallmechanicalproperties,wererecognizedbyusers.

简介：Surfacenanocrystallization(SNC)hasprovedtobeaneffectiveapproachtoimprovetheoverallpropertiesofbulkmetallicmaterials.Recently,anewsurfacenanocrystallizationtechnique,i.e.,surfacemechanicalgrindingtreatment(SMGT),wasdeveloped.Inthiswork,agradientnano-microstructurewasachievedinthesurfacelayeroftheAISI52100steelbyusingSMGT.Weobtainedaminimumgrainsizeofabout7nminthetopsurfacelayer.Thetotalthicknessofthedeformedlayerisover200micrometer.Meanwhilethesurfaceroughnessisratherlow.Ferritegrainsweredeformedtodifferentextentsvaryingwithdepthfromthetopsurface.Gradientgrainsizeswereformedfromtopsurfacetodeepmatrixwhichofferedagreatopportunitytostudytherefinementprocessoftheferritegrains.Itisfoundthatdislocationactivitiesplayadominantroleintheprocess.Attheinitiatestage,dislocationsaccumulatedandinteractedtoformdensedislocationwallsandcells.Increasingstrainandstrainrateinducedmoredislocationwallsincells,formingfinercells.Thisprocedurecontinueduntilnanograinsformedatthetopmostsurface.Theexistenceofcementiteparticlesinferritematrixgreatlyfacilitatestheferriterefinementprocess.Boundariesbetweenferritesandcementitesofferedmanydislocationsourceswhichacceleratethepropagationofdislocations.Dislocationwallswereblockedbycementiteswhichcertainlyleadtofinerdislocationcells.Theexistenceofcementitesmakesiteasiertogeneratefreshdislocationwallsinsub-microngrains.Astraingradientwasformedfromacementiteparticletosurroundingferritegrains.Thisstraingradientgivesrisetomoregeometricnecessarydislocations.Asferritegrainsizedecreasedlessthanthatofcementiteparticles,fragmentationoccurredincementites.Hardsecondphasewasusuallyconsideredasbrittle.Inthiswork,evidencesofdeformation(tracesofdislocationactivities)incementitesweredistinct.Sincethestressconcentrationinthephaseboundary(espec

简介：ThispaperpresentsanexperimentalinvestigationonanAISI316Lstainlesssteelregardingmechanicalproper-tiesandshortuniaxialcreeptestsatelevatedtemperatures.Theshorttimecreeptestswerecarriedoutunderdifferentbutconstantstresses.Theobtaineddataofultimatetensilestrength,yieldstrength,creepcurvesandeffectsofelevatedtemperaturesonmechanicalpropertieswerepresented.Foraselectedrheologicalmodel,materialparameterswereobtained.Asajustification,suchrheologicalmodelisimplementedinthefiniteelementprocedureforanuniaxiallystressedspecimeninselectedenvironmentalconditions.

简介：本文详细介绍了美国AISI标准:冷弯型钢骨架结构住宅设计规范(StandardforCold-FormedSteelFraming-Pre-scriptiveMcthodforOneandTwoFamilyDwellings)的主要内容.本部分包含的主要内容为墙体结构.

简介：冷弯型钢结构独立式或联体住宅在美国应用较多，技术已较成熟。AISI在多年研究工作的基础上，编制了冷弯型钢住宅的设计规范：StandardforCold-FormedSteelFraming-PrescriptiveMethodforOneandTwoFamilyDwellings。本文介绍的主要内容为：概述、连接、基础、楼面结构，今后将陆续介绍其余的内容。

简介：Thepresentstudyisconcernedwiththeeffectoffillermetalssuchasausteniticstainlesssteel,ferriticstainlesssteelandduplexstainlesssteelontensileandimpactpropertiesoftheferriticstainlesssteelconformingtoAISI409Mgrade.Rolledplatesof4mmthicknesswereusedasthebasematerialforpreparingsinglepassbuttweldedjoints.Tensileandimpactproperties,microhardness,microstructureandfracturesurfacemorphologyofthejointsfabricatedbyausteniticstainlesssteel,ferriticstainlesssteelandduplexstainlesssteelfillermetalswereevaluatedandtheresultswerereported.Fromthisinvestigation,itisfoundthatthejointsfabricatedbyduplexstainlesssteelfillermetalshowedhighertensilestrengthandhardnesscomparedtothejointsfabricatedbyausteniticandferriticstainlesssteelfillermetals.Jointsfabricatedbyausteniticstainlesssteelfillermetalexhibitedhigherductilityandimpacttoughnesscomparedwiththejointsfabricatedbyferriticstainlesssteelandduplexstainlesssteelfillermetals.

简介：Inthisstudy,resistancespotweldabilityof180gradebakehardeningsteel(BH180),7123gradeinterstitialfreesteel(IF7123)and304gradeausteniticstainlesssteel(AISI304L)witheachotherwasinvestigated.Inthejoiningprocess,electrodepressureandweldcurrentwerekeptconstantandsixdifferentweldtimewerechosen.Microstructure,microhardness,tensile-shearpropertiesandfracturetypesofresistancespotweldedjointswereexamined.Inordertocharacterizethemetallurgicalstructureoftheweldedjoint,themicrostructuralprofilewasdeveloped,andtherelationshipbetweenmechanicalpropertiesandmicrostructurewasdetermined.Thechangeofweldtime,nuggetdiameter,theHAZ(heataffectedzone)widthandtheelectrodeimmersiondepthwerealsoinvestigated.WeldedjointswereexaminedbySEM(scanningelectronmicroscopy)imagesoffracturesurface.Asaresultoftheexperiment,itwasdeterminedthatwithincreasingweldtime,tensileshearloadbearingcapacity(TLBC)increasedwithweldtimeupto25cycleandtwotypesoftearingoccurred.ItwasalsodeterminedthatwhilethefailureoccurredfromIFsideattheBH180+IF7123joint,itoccurredfromtheBH180sideattheBH180+AISI304Ljoint.

简介：利用硬质合金刀具,对奥氏体不锈钢AISI304进行了车削加工实验研究.讨论了车削速度对切屑形态、刀具磨损及工件表面粗糙度的影响.试验结果表明,随着切削速度的增大,切削热对切屑形态的影响降低,刀具后刀面磨损及工件表面粗糙度均减小.给出了不同切削速度下的切屑形态以及切削速度与刀具磨损、切削速度与表面粗糙度的关系曲线.

简介：摘要：通过对AISI4330V钢冶炼锻造后采用不同的热处理工艺研究其力学性能变化情况探索其最佳的热处理工艺。结果表明：Ac3+80℃正火、Ac3+40℃淬火、640℃高温回火工艺处理后AISI4330V钢的冲击吸收能量及延伸率较高，综合力学性能较好。屈服强度903MPa，抗拉强度1007MPa，延伸率20%，冲击吸收能量102J。

简介：

简介：奥氏体不锈钢、钴-铬合金、钛及其合金经常被用作医用植入材料.在这些金属材料中,奥氏体不锈钢是最常用的材料.然而,它在侵蚀性生物效应的长期作用下容易受到局部侵蚀.为了改进奥氏体不锈钢的抗磨损和耐腐蚀的效应,已经研究了几种不同的表面改性技术[1,2].本文的研究是采用具有耐腐蚀性的生物医学纳米涂层Al2O3涂复在奥氏体不锈钢AISI304的表面上,工艺中是采用溶胶-凝胶方法和浸入技术,并使用电化学极化进行测量.