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1/53封面2/53摘要本文综合分析了采用铸造工艺生产汽车发动机箱体的方法，从铸造设备、铸造模具设计、生产工艺、铸造生产中常见的问题及对策等多个角度，对铸造工艺的技术动向以及今后的研究课题提出了自己的见解。对国内外发动机箱体铸造生产进行了总结,其材质主要以C(质量分数,下同):3.15%~3.3%,CE:3.95%~4.05%,Si/C:0.6%~0.7%的灰铸铁为主。一般选择冲天炉-有芯工频电炉进行熔炼,孕育剂仍普遍采用75SiFe,立浇底注式浇注系统和保温冒口有利于获得优质箱体,冷芯制芯工艺已逐渐取代热芯工艺。通过提高浇注温度、型砂紧实率等措施可减少箱体常见缺陷渗漏的出现。铸造过程中合金配比工艺研究当箱体中含Cr量从0．308％上升到0．343％并不能明显增加珠光体数量和片间距的等级，但是可使铸件各部位的硬度总体呈上升趋势。铸件抗拉强度值上升幅度很大。一般可上升20～30MPa．在箱体中加入Sn可以明显提高铸件的布氏硬度和组织中的珠光体含量，但对于提高珠光体的片间距等级和减少渗碳体量则效果不明显。关键词：铸造工艺；灰铸铁；模具设计3/53ABSTRACTThispaperanalyzestheuseofthecastingprocesstoproduceautomobileengineboxapproachfrommanyanglescommonfoundryequipment,castingmolddesign,manufacturingprocess,castingproductionproblemsandcountermeasuresonthecastingprocesstechnologytrendsandfutureresearchputforwardtheirownviews.Fordomesticandengineblock,cylinderheadcastingasummary,thematerialmainlyC(massfraction):3.15%~3.3%,CE:3.95%~4.05%,Si/C:0.6%~0.7%ofgraycastironmain.Generallychoosecupola-acore-frequencyelectricfurnacesmelting,inoculantisstillwidelyused75SiFe,Lipouringbottomgatingandrisersystemisconducivetoqualityblock,cylinderheads,cold-coremakingprocesshasbeengraduallyreplacedbyheatcoreprocesses.Byincreasingthepouringtemperature,sandcompactionrateandothermeasurestoreducetheblock,cylinderheadscommondefectleakageoccurs.AlloyCastingprocess,whentheratioofthecylinderCrcontentincreasedfrom0.308%to0.343%didnotsignificantlyincreasethenumberandspacingofpearlitegrade,butcancastvariouspartsofhardnessoverallupwardtrend.Castingagreattensilestrengthvaluesrise.Generallyrise20~30MPa.AddingSninthecylindercansignificantlyimprovethecastingBrinellhardnessofpearlitecontentandorganization,butforimprovingthepearlitespacinglevelsandreducetheamountofcementiteisineffective.Keywords:casting;grayiron;molddesign4/53摘要........................................................................................................................2ABSTRACT...........................................................................................................31前言..................................................................................................................61．1课题背景...............................................................................................61．2箱体铸件国内外研究现状和发展趋势...............................................61．2．1国外发动机箱体铸造技术生产状况.....................................71．2．2我国发动机箱体铸件的生产状况.........................................71．3灰铸铁箱体材料的发展.......................................................................81．3．1箱体材料要求.........................................................................81．3．2灰铸铁箱体材料.....................................................................81．3．3灰铸铁的组织和几种合金元素的影响.................................91．3．4国内外箱体生产中灰铸铁材质的选择...............................151．4本课题研究的内容.............................................................................202低合金灰铸铁箱体工艺简介........................................................................212．1生产设备及原材料.............................................................................212．1．1生产设备...............................................................................212．2结构简介.............................................................................................212．3材质要求.............................................................................................232．4造型及浇注系统设计.........................................................................232．4．1造型工艺...............................................................................232．4．2浇注系统...............................................................................242．5制芯及组芯工艺方案设计.................................................................252．5．1制芯.......................................................................................252．5．2组芯.......................................................................................262．6孕育剂的加八方法.............................................................................282．6．1孕育机理及目的...................................................................282．6．2生产孕育铸铁铸件的条件...................................................282．7．1原材料...................................................................................293合金元素对发动机箱体性能的影响..............................................................303．1引言.....................................................................................................303．2试验装置及试验方法.........................................................................313．2．1试验装置...............................................................................313．2．2原材料...................................................................................313．2．3制样.......................................................................................313．3铬对箱体力学性能和金相组织的影响.............................................325/533．3．1试验目的及内容...................................................................323．3．2试验结果...............................................................................323．4锡对箱体力学性能和金相组织的影响..