銅(tong)(tong)合金具(ju)有(you)較高(gao)的(de)強度和塑性(xing),具(ju)有(you)高(gao)的(de)彈(dan)性(xing)極(ji)限(xian)(xian)和疲勞極(ji)限(xian)(xian),同時還具(ju)有(you)較好(hao)的(de)耐蝕性(xing)、抗(kang)堿性(xing)及優良的(de)減摩性(xing)和耐磨性(xing)。銅(tong)(tong)又(you)分純(chun)銅(tong)(tong)(俗稱紫銅(tong)(tong))、黃銅(tong)(tong)和青銅(tong)(tong)等。
1. 純銅
純銅(tong)(tong)(tong)面呈紫紅色,有良好(hao)的(de)導電性(xing)、導熱性(xing)和(he)耐(nai)大氣腐蝕性(xing),熔點為1083℃。在(zai)管(guan)道(dao)工程中常(chang)(chang)用(yong)純銅(tong)(tong)(tong)制成鋼管(guan)和(he)法蘭墊片。因純銅(tong)(tong)(tong)硬度(du)較低,退火后變得更柔(rou)軟,故(gu)常(chang)(chang)用(yong)作高壓管(guan)道(dao)中的(de)法蘭墊片。純銅(tong)(tong)(tong)管(guan)的(de)低溫(wen)性(xing)能比鋼材好(hao),故(gu)純銅(tong)(tong)(tong)管(guan)常(chang)(chang)用(yong)于(yu)(yu)空分(fen)設備管(guan)道(dao)、冷凍(dong)管(guan)道(dao)和(he)儀表管(guan)道(dao)。純銅(tong)(tong)(tong)的(de)高溫(wen)性(xing)能差,在(zai)120℃以(yi)下,容許抗(kang)拉強(qiang)度(du)為29.43MPa。溫(wen)度(du)若再升高,其機(ji)械強(qiang)度(du)則(ze)急劇(ju)下降,當溫(wen)度(du)上升至250℃時(shi),其容許抗(kang)拉強(qiang)度(du)只相當于(yu)(yu)常(chang)(chang)溫(wen)時(shi)的(de)2/3,已不(bu)宜在(zai)壓力下使(shi)用(yong)。常(chang)(chang)用(yong)的(de)純銅(tong)(tong)(tong)牌(pai)號(hao)為T2、T3、T4,雜(za)質(zhi)含量T2最(zui)少,T4最(zui)多。
2. 黃銅(H)(brass)(H)
黃(huang)(huang)(huang)銅是(shi)銅和鋅的(de)合金,其機械強(qiang)(qiang)度高,有(you)較好的(de)耐(nai)腐蝕(shi)性(xing)(xing)和澆(jiao)鑄(zhu)性(xing)(xing),可(ke)用來(lai)制作(zuo)管(guan)子、管(guan)件(jian)和閥(fa)(fa)門等。化工上常(chang)用的(de)有(you)H80、H68、H62(“H”是(shi)黃(huang)(huang)(huang)銅代號,后邊(bian)的(de)數字(zi)表示合金中銅的(de)平均(jun)含量)。H80比H68塑性(xing)(xing)好。作(zuo)強(qiang)(qiang)度計算時(shi)(shi),在120℃以下(xia),黃(huang)(huang)(huang)銅容許抗拉(la)強(qiang)(qiang)度為(wei)29.43MPa。隨著溫(wen)度升(sheng)高,其強(qiang)(qiang)度則急(ji)劇(ju)下(xia)降,當溫(wen)度沒超過225℃時(shi)(shi),黃(huang)(huang)(huang)銅閥(fa)(fa)件(jian)可(ke)用在壓力不(bu)超過1.6MPa的(de)管(guan)道中。
3. 青(qing)銅(tong)(bronze)(Q)
青(qing)銅是銅和錫(xi)的合金,又稱(cheng)錫(xi)青(qing)銅。由于錫(xi)的價格較高,故制(zhi)造(zao)青(qing)銅也常用(yong)(yong)其他元(yuan)素代替,因而又有無錫(xi)青(qing)銅,如鋁青(qing)銅、鉛青(qing)銅、硅青(qing)銅等。青(qing)銅通常由澆鑄而成(cheng),其強度、硬度及(ji)(ji)耐腐(fu)蝕性都比黃銅好(hao)。青(qing)銅常用(yong)(yong)于制(zhi)造(zao)蝸輪、齒輪、輪,以(yi)及(ji)(ji)管(guan)(guan)道工(gong)程中的閥件和管(guan)(guan)件等。
例如,制(zhi)冷系統空調器用銅配管的材(cai)料為(wei)磷(lin)脫氧(yang)無(wu)縫拉制(zhi)銅管,牌號為(wei)TP2(GB/T 5231),供應狀態有M(軟)、Y(硬),材(cai)料標記方(fang)法分別為(wei)TP2M,TP2Y。對應日本牌號分別為(wei)C1220T-OL,C1220-H。要求使用內表面(mian)無(wu)氧(yang)化的光亮管。其直徑、壁厚(hou)可(ke)參照GB/T 1804。其化學成(cheng)分分析方(fang)法按GB/T 5121進(jin)行,性能可(ke)按GB/T 228、GB/T 242、GB/T 246。