銅(tong)合金具(ju)有較高的強度和塑性(xing)(xing),具(ju)有高的彈性(xing)(xing)極限和疲(pi)勞極限,同時還具(ju)有較好的耐蝕性(xing)(xing)、抗堿性(xing)(xing)及優良的減摩性(xing)(xing)和耐磨性(xing)(xing)。銅(tong)又分(fen)純銅(tong)(俗稱紫(zi)銅(tong))、黃銅(tong)和青銅(tong)等。
1. 純(chun)銅
純(chun)(chun)銅面(mian)呈紫紅色(se),有(you)良好的(de)導電性、導熱(re)性和耐(nai)大氣腐(fu)蝕性,熔點為1083℃。在管(guan)(guan)道(dao)工程中常(chang)(chang)用(yong)純(chun)(chun)銅制成鋼管(guan)(guan)和法蘭墊(dian)片(pian)。因純(chun)(chun)銅硬度(du)(du)(du)(du)較低(di),退火后(hou)變得更柔軟,故常(chang)(chang)用(yong)作高壓(ya)管(guan)(guan)道(dao)中的(de)法蘭墊(dian)片(pian)。純(chun)(chun)銅管(guan)(guan)的(de)低(di)溫(wen)性能比鋼材好,故純(chun)(chun)銅管(guan)(guan)常(chang)(chang)用(yong)于(yu)空(kong)分(fen)設備管(guan)(guan)道(dao)、冷(leng)凍管(guan)(guan)道(dao)和儀表管(guan)(guan)道(dao)。純(chun)(chun)銅的(de)高溫(wen)性能差,在120℃以下,容(rong)許(xu)(xu)抗拉(la)強度(du)(du)(du)(du)為29.43MPa。溫(wen)度(du)(du)(du)(du)若(ruo)再升高,其機械(xie)強度(du)(du)(du)(du)則急劇下降,當(dang)溫(wen)度(du)(du)(du)(du)上升至(zhi)250℃時,其容(rong)許(xu)(xu)抗拉(la)強度(du)(du)(du)(du)只相當(dang)于(yu)常(chang)(chang)溫(wen)時的(de)2/3,已(yi)不宜在壓(ya)力下使用(yong)。常(chang)(chang)用(yong)的(de)純(chun)(chun)銅牌號為T2、T3、T4,雜質含(han)量(liang)T2最(zui)少,T4最(zui)多。
2. 黃銅(H)(brass)(H)
黃銅(tong)是(shi)銅(tong)和鋅的(de)(de)(de)合(he)金(jin)(jin),其機械強度(du)高,有較(jiao)好的(de)(de)(de)耐腐蝕性和澆鑄性,可用(yong)來制作管(guan)子、管(guan)件(jian)和閥門等。化工(gong)上常用(yong)的(de)(de)(de)有H80、H68、H62(“H”是(shi)黃銅(tong)代號,后(hou)邊的(de)(de)(de)數字表示合(he)金(jin)(jin)中(zhong)銅(tong)的(de)(de)(de)平(ping)均含量(liang))。H80比H68塑性好。作強度(du)計算時,在120℃以下(xia),黃銅(tong)容許抗拉強度(du)為29.43MPa。隨著溫度(du)升高,其強度(du)則急劇下(xia)降,當(dang)溫度(du)沒超(chao)過225℃時,黃銅(tong)閥件(jian)可用(yong)在壓力不超(chao)過1.6MPa的(de)(de)(de)管(guan)道中(zhong)。
3. 青銅(bronze)(Q)
青(qing)(qing)(qing)銅(tong)(tong)是銅(tong)(tong)和(he)錫(xi)(xi)的合金,又稱錫(xi)(xi)青(qing)(qing)(qing)銅(tong)(tong)。由于(yu)錫(xi)(xi)的價格較高,故(gu)制造(zao)青(qing)(qing)(qing)銅(tong)(tong)也常(chang)(chang)用其他元(yuan)素(su)代(dai)替,因而又有無錫(xi)(xi)青(qing)(qing)(qing)銅(tong)(tong),如鋁(lv)青(qing)(qing)(qing)銅(tong)(tong)、鉛青(qing)(qing)(qing)銅(tong)(tong)、硅青(qing)(qing)(qing)銅(tong)(tong)等。青(qing)(qing)(qing)銅(tong)(tong)通常(chang)(chang)由澆鑄(zhu)而成,其強度、硬(ying)度及耐腐蝕性都(dou)比黃銅(tong)(tong)好。青(qing)(qing)(qing)銅(tong)(tong)常(chang)(chang)用于(yu)制造(zao)蝸輪(lun)、齒輪(lun)、輪(lun),以及管(guan)道工(gong)程中的閥(fa)件(jian)和(he)管(guan)件(jian)等。
例如(ru),制冷(leng)系統(tong)空調器用銅配管的(de)材料(liao)為(wei)磷脫氧無縫拉制銅管,牌號為(wei)TP2(GB/T 5231),供應(ying)狀態有M(軟(ruan))、Y(硬),材料(liao)標(biao)記方(fang)法分(fen)別(bie)為(wei)TP2M,TP2Y。對應(ying)日本牌號分(fen)別(bie)為(wei)C1220T-OL,C1220-H。要求使用內(nei)表面無氧化的(de)光亮管。其直徑、壁厚可(ke)參照(zhao)GB/T 1804。其化學(xue)成(cheng)分(fen)分(fen)析方(fang)法按GB/T 5121進(jin)行,性能可(ke)按GB/T 228、GB/T 242、GB/T 246。