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)件(jian)(jian)的加工鑄(zhu)(zhu)造(zao)可以說有(you)許(xu)多種(zhong)工藝方法，現在使用較為廣泛的主要有(you)砂型(xing)(xing)鑄(zhu)(zhu)造(zao)、殼型(xing)(xing)鑄(zhu)(zhu)造(zao)、精密鑄(zhu)(zhu)造(zao)及陶瓷型(xing)(xing)鑄(zhu)(zhu)造(zao)。所有(you)這些(xie)鑄(zhu)(zhu)造(zao)工藝的共(gong)同點(dian)是(shi)，鑄(zhu)(zhu)型(xing)(xing)都(dou)設計有(you)澆(jiao)(jiao)(jiao)注系統，即熔融金屬進入型(xing)(xing)腔的通道(dao)；鑄(zhu)(zhu)型(xing)(xing)都(dou)是(shi)在每次澆(jiao)(jiao)(jiao)注完成后就被(bei)破壞掉。這些(xie)鑄(zhu)(zhu)造(zao)通道(dao)在砂型(xing)(xing)鑄(zhu)(zhu)造(zao)中被(bei)稱為直澆(jiao)(jiao)(jiao)道(dao)、橫澆(jiao)(jiao)(jiao)道(dao)及內澆(jiao)(jiao)(jiao)口(kou)，見圖2-1。鑄(zhu)(zhu)型(xing)(xing)是(shi)由型(xing)(xing)芯來形成鑄(zhu)(zhu)件(jian)(jian)的空腔和凹槽的。

  金屬液澆(jiao)注完(wan)畢之后，所得到的鑄件在(zai)(zai)出廠(chang)之前，還需要進行諸(zhu)如(ru)清理、檢驗、磨(mo)光以及在(zai)(zai)必要時進行的焊補和熱處理等后繼(ji)工序。

  鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)種(zhong)(zhong)類很(hen)多(duo)，按(an)造(zao)(zao)(zao)(zao)(zao)型(xing)(xing)(xing)(xing)方(fang)法習慣分為(wei)(wei)：①. 普通砂(sha)(sha)型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)，包括濕砂(sha)(sha)型(xing)(xing)(xing)(xing)、干(gan)砂(sha)(sha)型(xing)(xing)(xing)(xing)和化(hua)學硬化(hua)砂(sha)(sha)型(xing)(xing)(xing)(xing)三種(zhong)(zhong)類型(xing)(xing)(xing)(xing)；②. 特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)，按(an)造(zao)(zao)(zao)(zao)(zao)型(xing)(xing)(xing)(xing)材(cai)料又可分為(wei)(wei)以(yi)天然礦(kuang)產砂(sha)(sha)石為(wei)(wei)主要造(zao)(zao)(zao)(zao)(zao)型(xing)(xing)(xing)(xing)材(cai)料的特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)（如熔模(mo)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、泥型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)車(che)間殼型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、負壓鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、實型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、陶瓷型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)等）和以(yi)金(jin)屬為(wei)(wei)主要鑄(zhu)(zhu)型(xing)(xing)(xing)(xing)材(cai)料的特(te)種(zhong)(zhong)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)（如金(jin)屬型(xing)(xing)(xing)(xing)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、壓力鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、連續鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、低壓鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)、離(li)心(xin)鑄(zhu)(zhu)造(zao)(zao)(zao)(zao)(zao)等）兩種(zhong)(zhong)類型(xing)(xing)(xing)(xing)。

  鑄造是比(bi)較經濟的毛坯成型(xing)方(fang)法，對于形狀復雜的零(ling)(ling)件(jian)更能顯示出它的經濟性(xing)。如汽(qi)車發動機(ji)的缸(gang)體和(he)缸(gang)蓋，船舶螺旋槳以(yi)及(ji)精致的工(gong)藝藝術品等(deng)。有(you)些難以(yi)切削的零(ling)(ling)件(jian)，如燃氣輪機(ji)的鎳基合(he)金零(ling)(ling)件(jian)不用鑄造方(fang)法是無法成型(xing)的。

  另外(wai)，鑄(zhu)造(zao)的(de)零件(jian)尺寸和重量(liang)的(de)適應范(fan)圍很寬，金(jin)屬(shu)的(de)種類(lei)幾(ji)乎不受限制(zhi)；鑄(zhu)造(zao)零件(jian)在具有一般機械性(xing)能的(de)同時，還具有耐(nai)磨、耐(nai)腐蝕、吸震等綜合(he)性(xing)能，是其他金(jin)屬(shu)成型方(fang)法如鍛、軋、焊、沖壓(ya)等所達(da)不到的(de)。因此(ci)，在機器制(zhi)造(zao)業中(zhong)用鑄(zhu)造(zao)方(fang)法生產的(de)毛坯零件(jian)，在數量(liang)和噸位(wei)上(shang)迄(qi)今(jin)仍是最多的(de)。