一、銅是什么
銅（Cuprum）是(shi)一種金(jin)屬元(yuan)素，也是(shi)一種過渡元(yuan)素，化學符號Cu，英文copper，原子序數29。純銅是(shi)柔軟的(de)(de)金(jin)屬，表面剛(gang)切開時為紅橙(cheng)色(se)帶金(jin)屬光澤(ze)，單質呈紫紅色(se)。延(yan)展性(xing)好，導熱性(xing)和(he)導電性(xing)高，因(yin)此在電纜(lan)和(he)電氣(qi)、電子元(yuan)件是(shi)最常用(yong)的(de)(de)材(cai)料，也可(ke)用(yong)作(zuo)建筑材(cai)料，可(ke)以組成眾多種合金(jin)。銅合金(jin)機械性(xing)能優異，電阻率(lv)很低，其中最重要(yao)的(de)(de)數青銅和(he)黃銅。此外，銅也是(shi)耐用(yong)的(de)(de)金(jin)屬，可(ke)以多次(ci)回收而無損其機械性(xing)能。
二、銅的種類及用途
銅(tong)(tong)(tong)的種類主要有紫銅(tong)(tong)(tong)，黃(huang)銅(tong)(tong)(tong)，青銅(tong)(tong)(tong)和白(bai)銅(tong)(tong)(tong)四種。
1、紫銅
又名紅(hong)銅(tong)(tong)，是(shi)銅(tong)(tong)單質(zhi)，因(yin)其(qi)具有(you)玫瑰紅(hong)色(se)(se)，表面(mian)形成氧化(hua)膜后(hou)呈(cheng)紫(zi)(zi)色(se)(se)，故一(yi)般稱為紫(zi)(zi)銅(tong)(tong)。中(zhong)國紫(zi)(zi)銅(tong)(tong)加工材按成分可(ke)分為：普(pu)通紫(zi)(zi)銅(tong)(tong)（T1、T2、T3、T4）、無(wu)氧銅(tong)(tong)（TU1、TU2和高純、真空無(wu)氧銅(tong)(tong)）、脫(tuo)氧銅(tong)(tong)（TUP、TUMn）、添(tian)加少量合(he)金元素的特(te)種(zhong)銅(tong)(tong)（砷(shen)銅(tong)(tong)、碲銅(tong)(tong)、銀(yin)銅(tong)(tong)）四(si)類。紫(zi)(zi)銅(tong)(tong)具有(you)很好的導電(dian)(dian)性(xing)和導熱(re)性(xing)，塑(su)性(xing)極好，易于熱(re)壓和冷(leng)壓力加工，大量用于制(zhi)造電(dian)(dian)線、電(dian)(dian)纜、電(dian)(dian)刷、電(dian)(dian)火花專用電(dian)(dian)蝕(shi)銅(tong)(tong)等要求導電(dian)(dian)性(xing)良好的產(chan)品。
2、黃銅
黃(huang)(huang)(huang)銅(tong)(tong)是(shi)由(you)銅(tong)(tong)和鋅所組(zu)成的(de)合金，具有美觀的(de)黃(huang)(huang)(huang)色。由(you)銅(tong)(tong)、鋅組(zu)成的(de)黃(huang)(huang)(huang)銅(tong)(tong)就叫作(zuo)普通黃(huang)(huang)(huang)銅(tong)(tong)，如果是(shi)由(you)二種以上的(de)元素(su)組(zu)成的(de)多種合金就稱為特(te)殊黃(huang)(huang)(huang)銅(tong)(tong)。黃(huang)(huang)(huang)銅(tong)(tong)有較強的(de)耐(nai)磨性能(neng)，常被用于制造閥(fa)門、水管(guan)、空(kong)調內外機連接管(guan)和散熱器(qi)等。
3、青銅
青銅(tong)(tong)(tong)(tong)(tong)是(shi)金屬(shu)冶鑄(zhu)史上最早的合金，在純銅(tong)(tong)(tong)(tong)(tong)（紫(zi)(zi)銅(tong)(tong)(tong)(tong)(tong)）中加入錫(xi)(xi)或鉛的合金，有(you)特殊重要性(xing)和歷史意義，主要品種(zhong)有(you)錫(xi)(xi)青銅(tong)(tong)(tong)(tong)(tong)、鋁青銅(tong)(tong)(tong)(tong)(tong)、特殊青銅(tong)(tong)(tong)(tong)(tong)（又(you)稱高(gao)銅(tong)(tong)(tong)(tong)(tong)合金）。與純銅(tong)(tong)(tong)(tong)(tong)（紫(zi)(zi)銅(tong)(tong)(tong)(tong)(tong)）相(xiang)比(bi)，青銅(tong)(tong)(tong)(tong)(tong)強度高(gao)且熔(rong)(rong)點低（25%的錫(xi)(xi)冶煉(lian)青銅(tong)(tong)(tong)(tong)(tong)，熔(rong)(rong)點就會(hui)降(jiang)低到800℃。純銅(tong)(tong)(tong)(tong)(tong)（紫(zi)(zi)銅(tong)(tong)(tong)(tong)(tong)）的熔(rong)(rong)點為1083℃）。青銅(tong)(tong)(tong)(tong)(tong)鑄(zhu)造性(xing)好，耐磨且化學性(xing)質穩定，適用于鑄(zhu)造各(ge)種(zhong)器具(ju)、機械(xie)零件、軸承(cheng)、齒(chi)輪等(deng)。
4、白銅
白(bai)銅(tong)(tong)是以鎳為主要添加元(yuan)素的(de)銅(tong)(tong)基合金，呈銀(yin)(yin)白(bai)色(se)，有金屬(shu)光澤(ze)，故(gu)名白(bai)銅(tong)(tong)。銅(tong)(tong)鎳之間彼此可(ke)無限固溶，從而形成連續固溶體(ti)，即(ji)不論彼此的(de)比例多(duo)少，而恒為α-單相合金。當把鎳熔入(ru)紅(hong)銅(tong)(tong)里，含量(liang)超過16%以上時，產生(sheng)的(de)合金色(se)澤(ze)就變得潔白(bai)如銀(yin)(yin)，鎳含量(liang)越高(gao)，顏色(se)越白(bai)。白(bai)銅(tong)(tong)中鎳的(de)含量(liang)一般為25%。
銅(tong)鎳二(er)元合(he)金稱普通白(bai)(bai)(bai)銅(tong)；加有錳、鐵、鋅、鋁等元素(su)的(de)白(bai)(bai)(bai)銅(tong)合(he)金稱復雜白(bai)(bai)(bai)銅(tong)。工業用白(bai)(bai)(bai)銅(tong)分為結構(gou)白(bai)(bai)(bai)銅(tong)和電(dian)工白(bai)(bai)(bai)銅(tong)兩大類(lei)。結構(gou)白(bai)(bai)(bai)銅(tong)的(de)特點是機(ji)械(xie)性能和耐蝕性好，色(se)澤美觀(guan)。這(zhe)種白(bai)(bai)(bai)銅(tong)廣泛用於制(zhi)造精密(mi)機(ji)械(xie)、化(hua)工機(ji)械(xie)和船(chuan)舶構(gou)件。電(dian)工白(bai)(bai)(bai)銅(tong)一般(ban)有良(liang)好的(de)熱(re)(re)電(dian)性能。錳銅(tong)、康(kang)銅(tong)、考銅(tong)是含錳量不同的(de)錳白(bai)(bai)(bai)銅(tong)，是制(zhi)造精密(mi)電(dian)工儀器(qi)、變阻器(qi)、精密(mi)電(dian)阻、應變片、熱(re)(re)電(dian)偶(ou)等用的(de)材料(liao)。
三、黃銅青銅紫銅白銅哪個貴
在價格(ge)方面(mian)，紫銅最(zui)貴(gui)，白(bai)銅次(ci)之，隨(sui)后是青(qing)銅，最(zui)便(bian)宜的(de)是黃銅。不(bu)過最(zui)便(bian)宜的(de)也(ye)要比鐵(tie)貴(gui)出幾倍。
