銅(tong)合金(jin)具(ju)(ju)有較高(gao)的(de)(de)強度和(he)塑性(xing)(xing),具(ju)(ju)有高(gao)的(de)(de)彈性(xing)(xing)極限(xian)和(he)疲勞極限(xian),同(tong)時還具(ju)(ju)有較好的(de)(de)耐蝕性(xing)(xing)、抗(kang)堿性(xing)(xing)及優良的(de)(de)減摩性(xing)(xing)和(he)耐磨性(xing)(xing)。銅(tong)又分純(chun)銅(tong)(俗稱紫(zi)銅(tong))、黃銅(tong)和(he)青銅(tong)等。


1. 純銅(tong)


  純(chun)銅面(mian)呈紫(zi)紅色,有良(liang)好的導(dao)電性、導(dao)熱性和耐(nai)大氣腐(fu)蝕性,熔(rong)點為1083℃。在(zai)管(guan)(guan)(guan)(guan)道(dao)(dao)工程中(zhong)常(chang)用純(chun)銅制成鋼(gang)管(guan)(guan)(guan)(guan)和法蘭(lan)墊(dian)片(pian)。因(yin)純(chun)銅硬度(du)較低(di),退火后變得更柔軟,故常(chang)用作高(gao)(gao)壓(ya)管(guan)(guan)(guan)(guan)道(dao)(dao)中(zhong)的法蘭(lan)墊(dian)片(pian)。純(chun)銅管(guan)(guan)(guan)(guan)的低(di)溫(wen)性能比鋼(gang)材(cai)好,故純(chun)銅管(guan)(guan)(guan)(guan)常(chang)用于(yu)空分(fen)設備(bei)管(guan)(guan)(guan)(guan)道(dao)(dao)、冷凍管(guan)(guan)(guan)(guan)道(dao)(dao)和儀表(biao)管(guan)(guan)(guan)(guan)道(dao)(dao)。純(chun)銅的高(gao)(gao)溫(wen)性能差,在(zai)120℃以下,容許抗拉強度(du)為29.43MPa。溫(wen)度(du)若再升高(gao)(gao),其(qi)機械強度(du)則急劇(ju)下降,當(dang)溫(wen)度(du)上(shang)升至250℃時,其(qi)容許抗拉強度(du)只相當(dang)于(yu)常(chang)溫(wen)時的2/3,已(yi)不(bu)宜在(zai)壓(ya)力下使用。常(chang)用的純(chun)銅牌號為T2、T3、T4,雜質(zhi)含(han)量T2最少,T4最多。


2. 黃銅(tong)(H)(brass)(H)


  黃銅(tong)是銅(tong)和鋅的合金,其(qi)機(ji)械強(qiang)度(du)高(gao)(gao),有較好(hao)的耐腐(fu)蝕(shi)性和澆鑄(zhu)性,可用來制作(zuo)管子、管件和閥門等。化(hua)工上常(chang)用的有H80、H68、H62(“H”是黃銅(tong)代號,后邊的數字表示合金中銅(tong)的平均(jun)含量)。H80比(bi)H68塑性好(hao)。作(zuo)強(qiang)度(du)計算時,在120℃以下,黃銅(tong)容許抗拉強(qiang)度(du)為29.43MPa。隨著溫(wen)度(du)升高(gao)(gao),其(qi)強(qiang)度(du)則急劇下降,當溫(wen)度(du)沒超過225℃時,黃銅(tong)閥件可用在壓力(li)不超過1.6MPa的管道中。


3. 青(qing)銅(tong)(bronze)(Q)


  青(qing)(qing)銅(tong)(tong)是銅(tong)(tong)和(he)錫的(de)合金,又(you)稱錫青(qing)(qing)銅(tong)(tong)。由(you)于(yu)(yu)錫的(de)價格較(jiao)高,故制(zhi)造青(qing)(qing)銅(tong)(tong)也常用(yong)(yong)其他元素代替,因而(er)又(you)有無錫青(qing)(qing)銅(tong)(tong),如鋁青(qing)(qing)銅(tong)(tong)、鉛青(qing)(qing)銅(tong)(tong)、硅青(qing)(qing)銅(tong)(tong)等。青(qing)(qing)銅(tong)(tong)通常由(you)澆鑄(zhu)而(er)成,其強(qiang)度、硬(ying)度及(ji)耐腐(fu)蝕性都(dou)比黃銅(tong)(tong)好。青(qing)(qing)銅(tong)(tong)常用(yong)(yong)于(yu)(yu)制(zhi)造蝸輪、齒輪、輪,以及(ji)管(guan)道工程中的(de)閥(fa)件(jian)和(he)管(guan)件(jian)等。


  例如(ru),制冷(leng)系統空調器用銅配(pei)管的材料為(wei)磷脫(tuo)氧無縫拉制銅管,牌號為(wei)TP2(GB/T 5231),供(gong)應狀態有M(軟(ruan))、Y(硬),材料標記方法(fa)(fa)分(fen)(fen)別為(wei)TP2M,TP2Y。對應日本(ben)牌號分(fen)(fen)別為(wei)C1220T-OL,C1220-H。要求使用內表(biao)面(mian)無氧化的光亮(liang)管。其直徑、壁厚可(ke)參(can)照GB/T 1804。其化學(xue)成分(fen)(fen)分(fen)(fen)析方法(fa)(fa)按(an)GB/T 5121進行,性能(neng)可(ke)按(an)GB/T 228、GB/T 242、GB/T 246。