一、銅是什么
銅(tong)（Cuprum）是一種金(jin)(jin)屬(shu)元(yuan)素(su)，也是一種過渡元(yuan)素(su)，化(hua)學符號Cu，英(ying)文copper，原子(zi)序數29。純銅(tong)是柔軟的金(jin)(jin)屬(shu)，表面剛切(qie)開時為紅橙色帶(dai)金(jin)(jin)屬(shu)光澤，單質(zhi)呈紫紅色。延展性好(hao)，導熱(re)性和(he)導電(dian)(dian)性高，因此在電(dian)(dian)纜和(he)電(dian)(dian)氣、電(dian)(dian)子(zi)元(yuan)件是最(zui)常(chang)用的材(cai)料(liao)，也可用作(zuo)建筑材(cai)料(liao)，可以組(zu)成眾多種合金(jin)(jin)。銅(tong)合金(jin)(jin)機械性能優異，電(dian)(dian)阻率很低，其中最(zui)重要(yao)的數青(qing)銅(tong)和(he)黃(huang)銅(tong)。此外，銅(tong)也是耐用的金(jin)(jin)屬(shu)，可以多次回(hui)收而無損其機械性能。
二、銅的種類及用途
銅(tong)的種(zhong)類主要有紫(zi)銅(tong)，黃銅(tong)，青銅(tong)和白銅(tong)四種(zhong)。
1、紫銅
又(you)名紅銅(tong)，是銅(tong)單質(zhi)，因其具有玫瑰(gui)紅色，表面形成氧化膜后呈紫(zi)(zi)色，故一般(ban)稱為(wei)(wei)紫(zi)(zi)銅(tong)。中國紫(zi)(zi)銅(tong)加(jia)工材按成分可分為(wei)(wei)：普通紫(zi)(zi)銅(tong)（T1、T2、T3、T4）、無(wu)(wu)氧銅(tong)（TU1、TU2和高純、真空(kong)無(wu)(wu)氧銅(tong)）、脫氧銅(tong)（TUP、TUMn）、添(tian)加(jia)少量合金元素(su)的特種銅(tong)（砷銅(tong)、碲銅(tong)、銀銅(tong)）四類。紫(zi)(zi)銅(tong)具有很好的導(dao)電(dian)(dian)性(xing)和導(dao)熱性(xing)，塑性(xing)極好，易于熱壓(ya)和冷壓(ya)力(li)加(jia)工，大量用于制造(zao)電(dian)(dian)線、電(dian)(dian)纜(lan)、電(dian)(dian)刷(shua)、電(dian)(dian)火花(hua)專用電(dian)(dian)蝕銅(tong)等要(yao)求導(dao)電(dian)(dian)性(xing)良好的產品。
2、黃銅
黃銅(tong)是(shi)由銅(tong)和(he)鋅(xin)所組(zu)成(cheng)的(de)合金，具有美觀(guan)的(de)黃色。由銅(tong)、鋅(xin)組(zu)成(cheng)的(de)黃銅(tong)就叫作普通黃銅(tong)，如(ru)果是(shi)由二種以上的(de)元素組(zu)成(cheng)的(de)多種合金就稱為(wei)特殊黃銅(tong)。黃銅(tong)有較強的(de)耐磨性能(neng)，常被用于(yu)制造閥(fa)門、水管、空調內外機連(lian)接管和(he)散熱(re)器等。
3、青銅
青(qing)(qing)銅(tong)(tong)(tong)是金(jin)(jin)屬冶鑄(zhu)史上最早的(de)合(he)(he)金(jin)(jin)，在純銅(tong)(tong)(tong)（紫銅(tong)(tong)(tong)）中加入錫或鉛的(de)合(he)(he)金(jin)(jin)，有特殊(shu)重要性(xing)和歷(li)史意義，主要品種有錫青(qing)(qing)銅(tong)(tong)(tong)、鋁青(qing)(qing)銅(tong)(tong)(tong)、特殊(shu)青(qing)(qing)銅(tong)(tong)(tong)（又稱高銅(tong)(tong)(tong)合(he)(he)金(jin)(jin)）。與純銅(tong)(tong)(tong)（紫銅(tong)(tong)(tong)）相比(bi)，青(qing)(qing)銅(tong)(tong)(tong)強度高且熔(rong)(rong)點低(di)（25%的(de)錫冶煉青(qing)(qing)銅(tong)(tong)(tong)，熔(rong)(rong)點就會(hui)降低(di)到800℃。純銅(tong)(tong)(tong)（紫銅(tong)(tong)(tong)）的(de)熔(rong)(rong)點為1083℃）。青(qing)(qing)銅(tong)(tong)(tong)鑄(zhu)造性(xing)好，耐磨(mo)且化學性(xing)質穩定，適用于鑄(zhu)造各種器具、機(ji)械零件、軸(zhou)承、齒輪等。
4、白銅
白(bai)銅(tong)(tong)(tong)是(shi)以鎳(nie)為主要添(tian)加(jia)元素的(de)銅(tong)(tong)(tong)基合金(jin)(jin)(jin)(jin)，呈(cheng)銀白(bai)色，有(you)金(jin)(jin)(jin)(jin)屬(shu)光澤，故名白(bai)銅(tong)(tong)(tong)。銅(tong)(tong)(tong)鎳(nie)之間(jian)彼此可無(wu)限固溶(rong)，從(cong)而形成連續(xu)固溶(rong)體(ti)，即(ji)不論彼此的(de)比例多少，而恒(heng)為α-單相(xiang)合金(jin)(jin)(jin)(jin)。當把鎳(nie)熔(rong)入(ru)紅銅(tong)(tong)(tong)里，含(han)量超過16%以上時(shi)，產生的(de)合金(jin)(jin)(jin)(jin)色澤就變得潔(jie)白(bai)如銀，鎳(nie)含(han)量越高(gao)，顏色越白(bai)。白(bai)銅(tong)(tong)(tong)中鎳(nie)的(de)含(han)量一般為25%。
銅(tong)(tong)鎳二元合金(jin)稱普通白(bai)銅(tong)(tong)；加(jia)有錳(meng)、鐵、鋅、鋁等元素的(de)白(bai)銅(tong)(tong)合金(jin)稱復雜白(bai)銅(tong)(tong)。工業(ye)用白(bai)銅(tong)(tong)分為結(jie)構白(bai)銅(tong)(tong)和(he)電(dian)工白(bai)銅(tong)(tong)兩大類。結(jie)構白(bai)銅(tong)(tong)的(de)特(te)點是(shi)(shi)機(ji)械性能(neng)(neng)和(he)耐蝕性好，色澤(ze)美觀。這種白(bai)銅(tong)(tong)廣泛用於制(zhi)造精(jing)密(mi)機(ji)械、化工機(ji)械和(he)船舶構件。電(dian)工白(bai)銅(tong)(tong)一般(ban)有良(liang)好的(de)熱電(dian)性能(neng)(neng)。錳(meng)銅(tong)(tong)、康銅(tong)(tong)、考銅(tong)(tong)是(shi)(shi)含錳(meng)量不同(tong)的(de)錳(meng)白(bai)銅(tong)(tong)，是(shi)(shi)制(zhi)造精(jing)密(mi)電(dian)工儀器(qi)、變阻器(qi)、精(jing)密(mi)電(dian)阻、應變片、熱電(dian)偶(ou)等用的(de)材(cai)料(liao)。
三、黃銅青銅紫銅白銅哪個貴
在價格方面，紫銅最貴，白銅次(ci)之(zhi)，隨(sui)后是(shi)青(qing)銅，最便(bian)宜的是(shi)黃(huang)銅。不過最便(bian)宜的也(ye)要比鐵貴出幾(ji)倍。
