鑄造是將金屬熔煉成符合一定要求的液體并澆入鑄型內,經冷卻凝固、清整處理后得到有預定形狀、尺寸和性能的鑄件的工藝過程。


  鑄(zhu)(zhu)(zhu)件的(de)加工(gong)鑄(zhu)(zhu)(zhu)造(zao)(zao)可以(yi)說有許多種工(gong)藝方法,現(xian)在使用較為廣(guang)泛的(de)主要有砂(sha)型(xing)(xing)(xing)鑄(zhu)(zhu)(zhu)造(zao)(zao)、殼(ke)型(xing)(xing)(xing)鑄(zhu)(zhu)(zhu)造(zao)(zao)、精密鑄(zhu)(zhu)(zhu)造(zao)(zao)及陶瓷型(xing)(xing)(xing)鑄(zhu)(zhu)(zhu)造(zao)(zao)。所有這些(xie)(xie)鑄(zhu)(zhu)(zhu)造(zao)(zao)工(gong)藝的(de)共同點是,鑄(zhu)(zhu)(zhu)型(xing)(xing)(xing)都設計有澆(jiao)(jiao)注系統,即(ji)熔融(rong)金(jin)屬進入型(xing)(xing)(xing)腔(qiang)的(de)通(tong)道(dao)(dao);鑄(zhu)(zhu)(zhu)型(xing)(xing)(xing)都是在每次澆(jiao)(jiao)注完成(cheng)后(hou)就被破壞掉。這些(xie)(xie)鑄(zhu)(zhu)(zhu)造(zao)(zao)通(tong)道(dao)(dao)在砂(sha)型(xing)(xing)(xing)鑄(zhu)(zhu)(zhu)造(zao)(zao)中被稱為直澆(jiao)(jiao)道(dao)(dao)、橫澆(jiao)(jiao)道(dao)(dao)及內(nei)澆(jiao)(jiao)口(kou),見圖(tu)2-1。鑄(zhu)(zhu)(zhu)型(xing)(xing)(xing)是由(you)型(xing)(xing)(xing)芯來形成(cheng)鑄(zhu)(zhu)(zhu)件的(de)空腔(qiang)和凹(ao)槽的(de)。


圖 1.jpg


  金屬液澆注完畢之(zhi)(zhi)后,所(suo)得到(dao)的鑄件(jian)在出廠(chang)之(zhi)(zhi)前(qian),還(huan)需要(yao)進(jin)行諸如清理、檢驗(yan)、磨光(guang)以及(ji)在必要(yao)時進(jin)行的焊(han)補和熱處理等(deng)后繼工序(xu)。


  鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)種(zhong)(zhong)類(lei)很多,按(an)造(zao)(zao)(zao)(zao)型(xing)(xing)方法習慣分(fen)(fen)為:①. 普(pu)通砂型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao),包括濕砂型(xing)(xing)、干(gan)砂型(xing)(xing)和化學硬化砂型(xing)(xing)三種(zhong)(zhong)類(lei)型(xing)(xing);②. 特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao),按(an)造(zao)(zao)(zao)(zao)型(xing)(xing)材料又可(ke)分(fen)(fen)為以天然礦產砂石(shi)為主(zhu)要造(zao)(zao)(zao)(zao)型(xing)(xing)材料的特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(如(ru)(ru)熔(rong)模鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、泥型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)車間殼型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、負(fu)壓鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、實(shi)型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、陶瓷型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)等)和以金(jin)屬為主(zhu)要鑄(zhu)(zhu)型(xing)(xing)材料的特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(如(ru)(ru)金(jin)屬型(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、壓力鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、連(lian)續鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、低壓鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)、離(li)心鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)等)兩種(zhong)(zhong)類(lei)型(xing)(xing)。


  鑄造(zao)是比較經(jing)濟(ji)的毛坯成(cheng)(cheng)型方法,對于(yu)形狀(zhuang)復雜(za)的零件(jian)(jian)更能顯示出(chu)它的經(jing)濟(ji)性(xing)。如(ru)汽車發(fa)動機(ji)的缸體和(he)缸蓋,船舶螺(luo)旋槳以(yi)及精致的工(gong)藝(yi)藝(yi)術品等。有(you)些(xie)難以(yi)切削的零件(jian)(jian),如(ru)燃(ran)氣輪機(ji)的鎳基合金零件(jian)(jian)不用鑄造(zao)方法是無法成(cheng)(cheng)型的。


  另外,鑄造(zao)(zao)的(de)(de)零件(jian)尺寸和重量(liang)的(de)(de)適(shi)應范圍很寬,金屬的(de)(de)種類幾乎不受限制;鑄造(zao)(zao)零件(jian)在具有一般機械性(xing)能(neng)的(de)(de)同時,還具有耐磨、耐腐蝕、吸震(zhen)等綜(zong)合性(xing)能(neng),是其他金屬成型方(fang)法(fa)如鍛、軋、焊(han)、沖壓等所達不到的(de)(de)。因此,在機器制造(zao)(zao)業中用鑄造(zao)(zao)方(fang)法(fa)生產的(de)(de)毛坯零件(jian),在數量(liang)和噸位上迄今仍(reng)是最(zui)多(duo)的(de)(de)。