ForgingprocessesForgingprocessesForgingProcessesHistoryofForging？Forgingisoneoftheoldestknownmetalworkingprocesses.Traditionally,forgingwasperformedbya

smith

usinghammerand

anvil(鐵砧),thoughintroducingwaterpowertotheproductionandworkingofironinthe12thcenturydrovethehammerandanvilintoobsolescence(過時，淘汰).Video-hammerandanvilForgingProcessesHistoryofUnit4ForgingProcesses

WhatisForging？Itisanimportanthot-formingprocess.Itisusedinproducingcomponentsofallshapesandsizes,fromquitesmallitemstolargeunitsweighingseveraltons.鍛造是一種重要的熱成型工藝。用于生產各種形狀和尺寸的零件，有的極小有的重達幾噸。Itistheprocessbywhichmetalisheatedandisshapedbyplasticdeformationbysuitablyapplyingcompressiveforce.在此過程中金屬被加熱，通過適當應用壓力產生塑性變形使金屬成型。(video-largepartsforging)Unit4ForgingProcessesWh

Handforgingtoolscomprisevariouslyshaped

hammers.手工鍛造工具包括各種不同形狀的錘子。①Forthesemimechanizedforgingofsmalltomedium-sizedcomponents,forginghammerspoweredbyvariousmeansareemployed.對小到中等尺寸零件的半機械化鍛造而言，采用鍛錘，鍛錘的驅動動力有多種方式。video-swordThefeaturecommontoallofthemisthat,likethehandforginghammer,theyutilizetheenergyofafallingweighttodevelopthepressureneededforshapingthemetal.無論采用什么樣的驅動力，它們共同的特點就是(和手工鍛錘一樣)，都是利用落重能量來產生金屬成型所需的壓力。ForgingtoolsHandforgingtoolscomprisev②Largercomponentsareforgedbymeansofforgingpressesoperatedbysteamorcompressedairorbyhydraulicorelectricpower.鍛造大零件則要用到蒸汽、壓縮空氣、液力或電力驅動的鍛壓機。Largelyautomaticforgingmachinesareusedforthequantityproductionofengineeringparts.大型的自動化鍛機用于工程零件的批量生產。Forgingtools②LargercomponentsareforgedClassificationofforgingTherearemanydifferentkindsofforgingprocessesavailable,howevertheycanbegroupedintothreemainclasses:Drawnout:lengthincreases,cross-section

decreasesUpset:lengthdecreases,cross-sectionincreasesSqueezedinclosedcompressiondies:producesmultidirectionalflowDrawnout拔長cross-section橫截面Upset鐓粗Squeezed擠壓,塞進

compressiondies壓模closedcompressiondies封閉壓模Video-拔長ClassificationofforgingVideoDropForging落鍛，落錘鍛造Open-DieForging/HandForging開模段，手工鍛，自由鍛Closed-DieForging/Impression-DieForging/PrecisionForging閉模鍛，模鍛，精鍛PressForgings

壓力鍛造UpsetForgings頂鍛，鐓鍛RollForgings滾鍛,輥鍛Swaging（型鍛,模鍛,擠鍛）NetShape/Near-NetShapeForgings精鍛,純型鍛CommonForgingProcessesDropForging落鍛，落錘鍛造CommonForDropforgingisaforgingprocesswhereahammerisraisedandthen"dropped"ontotheworkpiecetodeformitaccordingtotheshapeofthedie.落鍛過程即鍛錘抬起再“落下”，落至工件使之變形。Therearetwotypesofdropforging:open-diedropforgingandclosed-diedropforging.有兩種落鍛：開模落鍛和閉模落鍛Asthenamesimply,thedifferenceisintheshapeofthedie,withtheformernotfullyenclosingtheworkpiece,whilethelatterdoes.顧名思義，兩者之間區別在于模具的形狀。開模鍛沒有完全封閉式包圍工件，閉模鍛卻有。DropForging落鍛，落錘鍛造DropforgingisaforgingprocOpen-dieforgingisalsoknownas

smithforging.開模鍛（自由鍛）又稱為鐵匠的鍛造Inopen-dieforging,ahammerstrikesanddeformstheworkpiece,whichisplacedonastationaryanvil.在開模鍛中，工件放置在固定的鐵砧上，由鐵錘擊打工件使之變形，Open-dieforginggetsitsnamefromthefactthatthedies(thesurfacesthatareincontactwiththeworkpiece)donotenclosetheworkpiece,allowingittoflowexceptwherecontactedbythedies.開模鍛得名是因為模具沒有封閉工件，使得工件可以自由流動（與模具接觸的地方除外）1.open-dieforging開模段，手工鍛，自由鍛Open-dieforgingisalsoknownTherefore,theoperator,needstoorientandpositiontheworkpiecetogetthedesiredshape.

因此操作者需要對工件進行定位和放置動作，才能獲得需要的形狀。1.open-dieforging開模段，手工鍛，自由鍛Therefore,theoperator,needsThediesareusuallyflatinshape,butsomehaveaspeciallyshapedsurfaceforspecializedoperations.Forexample,adiemayhavearound,concave,orconvexsurfaceorbeatooltoformholesorbeacut-offtool.自由鍛的模具通常是平面，但在特殊操作中也會用到特殊形狀表面。例如圓形表面，凹面，凸面，或是制孔工具，切斷工具。1.open-dieforging開模段，手工鍛，自由鍛ThediesareusuallyflatinsOpen-dieforgingscanbeworkedintoshapeswhichincludediscs,hubs,blocks,shafts(includingstepshaftsorwithflanges),sleeves,cylinders,flats,hexes,rounds,plate,andsomecustomshapes.自由鍛件可以被加工為各種形狀，包括閥盤，襯套，塊，軸(包括階梯軸或帶法蘭盤的軸)，套筒，圓柱體，平板，六角形，圓形物，盤類，及一些自定義形狀。1.open-dieforging開模段，手工鍛，自由鍛Video-球體Open-dieforgingscanbeworke

Open-dieforginglendsitselfto

shortrunsandisappropriateforartsmithingandcustomwork.手工鍛適用于小批量生產，藝術鍛造，及定制工作。Insomecases,open-dieforgingmaybeemployedtorough-shapeingots

topreparethemforsubsequentoperations.在一些情況下，自由鍛被用于為機械加工等后續操作準備粗略成型的坯料。lenditselfto適宜于shortrun小批量Ingot錠，鑄塊1.open-dieforging開模段，手工鍛，自由鍛

Open-dieforginglendsitselfItisverywidelyusedformassproduction

inindustry,inwhichthemetalisshapedbypressingbetweenapairofforgingdies.閉模鍛廣泛用于工業大批量生產，金屬在一對鍛模之間擠壓成型。

Makeup：Theupperdieisusuallyattachedtotheram（撞頭）ofaforgingpressoraforginghammer,whilethelowerdieisstationary.Togethertheyformacloseddie.Themetalisplacedinthelowerdie.組成：頂模通常附著在鍛壓機的撞頭或鍛錘上，底模則固定不動。金屬就放置在底模上。2.closed-dieforging/Impression-dieforgingItisverywidelyusedformasThehammeristhendroppedontheworkpiece,causingthemetaltoflowandfillthediecavities.鍛錘落至工件，使得金屬流動并填充模具模膛。Thehammerisgenerallyincontactwiththeworkpieceonthescaleofmilliseconds.Dependingonthesizeandcomplexityofthepart,thehammermaybedroppedmultipletimesinquicksuccession.通常鍛錘和工件接觸的速度以毫秒計。根據零件的尺寸和復雜性，鍛錘快速連續地多次落錘。2.closed-dieforging/Impression-dieforgingThehammeristhendroppedonExcessmetalissqueezedoutofthediecavities,formingwhatisreferredtoas"flash".多余的金屬從模具模膛中擠出，形成所謂的“飛邊”。Theflashcoolsmorerapidlythantherestofthematerial;thiscoolmetalisstrongerthanthemetalinthedie,soithelpspreventmoreflashfromforming.飛邊的冷卻速度比其余速度快。冷卻后的飛邊比模具內的金屬強度大，從而防止形成更多的飛邊。Thisalsoforcesthemetaltocompletelyfillthediecavity.Afterforging,theflashisremoved.這也有助于金屬完全填充模具模膛。鍛造后，要將飛邊去除。2.closed-dieforging/Impression-dieforgingExcessmetalissqueezedoutoIncommercialimpression-dieforging,theworkpieceisusuallymovedthroughaseriesofcavitiesinadietogetfromaningottothefinalform.大多數的商用閉模鍛件，工件從鑄錠到成品實際是連續流經一個模具中的多個模膛的過程。(多膛鍛模)Thefirstimpressionisusedtodistributethemetalintotheroughshapeinaccordancetotheneedsoflatercavities;thisimpressioniscalledan"edging","fullering",or"bending"impression.第一種模膛(制坯模膛)將金屬鍛造為與后續模膛的需要粗略一致的形狀。這種模膛被稱為“切斷模膛”,“成型模膛”,“彎曲模膛”等。2.closed-dieforging/Impression-dieforgingIncommercialimpression-diefThefirstimpression:2.closed-dieforging/Impression-dieforgingThefirstimpression:2.closedThefollowingcavitiesarecalled"blocking"cavities,inwhichthepieceisworkingintoashapethatmorecloselyresemblesthefinalproduct.下一個模膛叫“預鍛模膛”，工件在這里被加工至與最終產品更加接近。Thefinalshapeisforgedina"final"or"finisher"impressioncavity.Ifthereisonlyashortrunofpartstobedone,thenitmaybemoreeconomicalforthedietolackafinalimpressioncavityandinsteadmachinethefinalfeatures.最后的形狀在“終鍛模膛”中鍛造獲得。如果是進行小批量生產，則更經濟的做法是在模具中不設終鍛模膛而改用機械加工獲取最終的產品特征。2.closed-dieforging/Impression-dieforgingThefollowingcavitiesarecalclosed-dieforging

aseriesofcavitiesclosed-dieforging

aseriesoAdvantage：canproducecomponentsofgreatercomplexityandaccuracy,withabettersurfacefinish,thanthemoretraditionalmethodsnotusingcloseddies.2.closed-dieforging/Impression-dieAdvantage：canproducecomponen1.thehydraulicforgingpressisamoreexpensivepieceof

e