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來源:行(xing)業動態(tai) 閱讀:109428 發布時間:2019-07-05
導讀:由(you)于(yu)生(sheng)(sheng)產(chan)(chan)銅(tong)桿(gan)(gan)的兩者的工(gong)藝不(bu)同,所生(sheng)(sheng)產(chan)(chan)的銅(tong)桿(gan)(gan)中(zhong)的含氧(yang)(yang)量及外觀就不(bu)同。上(shang)引生(sheng)(sheng)產(chan)(chan)的銅(tong)桿(gan)(gan),工(gong)藝得當氧(yang)(yang)含量在10ppm以下(xia)(xia),叫無氧(yang)(yang)銅(tong)桿(gan)(gan);連鑄連鑄生(sheng)(sheng)產(chan)(chan)的銅(tong)桿(gan)(gan) 是在保(bao)護(hu)條件下(xia)(xia)的熱軋,氧(yang)(yang)含量在200-500ppm范圍內,但有時(shi)也(ye)高(gao)達700ppm以上(shang),一般(ban)情況下(xia)(xia),此種方法生(sheng)(sheng)產(chan)(chan)的銅(tong)外表光亮,低氧(yang)(yang)銅(tong)桿(gan)(gan),有時(shi)也(ye)叫光桿(gan)(gan)。
銅(tong)(tong)桿是電(dian)纜行(xing)(xing)業的主要原料,生(sheng)產(chan)的方(fang)式主要有兩種——連(lian)鑄(zhu)(zhu)連(lian)軋(ya)法(fa)和上引(yin)(yin)(yin)連(lian)鑄(zhu)(zhu)法(fa)。連(lian)鑄(zhu)(zhu)連(lian)軋(ya)低(di)氧(yang)銅(tong)(tong)桿的生(sheng)產(chan)方(fang)法(fa)較多,其特點(dian)是金屬(shu)在(zai)(zai)豎爐(lu)(lu)中(zhong)融化(hua)后(hou),銅(tong)(tong)液通(tong)過保溫爐(lu)(lu)、溜(liu)槽、中(zhong)間(jian)包(bao),從澆(jiao)管進入封閉的模(mo)腔內(nei),采(cai)(cai)用較大的冷(leng)(leng)卻強度進行(xing)(xing)冷(leng)(leng)卻,形成鑄(zhu)(zhu)坯(pi),然后(hou)進行(xing)(xing)多道次(ci)軋(ya)制,生(sheng)產(chan)的低(di)氧(yang)銅(tong)(tong)桿為(wei)熱加(jia)(jia)工(gong)組織(zhi),原來的鑄(zhu)(zhu)造(zao)(zao)組織(zhi)已經破碎,含(han)氧(yang)量一(yi)般為(wei)200~400ppm之間(jian)。無氧(yang)銅(tong)(tong)桿國內(nei)基本全部采(cai)(cai)用上引(yin)(yin)(yin)連(lian)鑄(zhu)(zhu)法(fa)生(sheng)產(chan),金屬(shu)在(zai)(zai)感應電(dian)爐(lu)(lu)中(zhong)融化(hua)后(hou)通(tong)過石墨模(mo)進行(xing)(xing)上引(yin)(yin)(yin)連(lian)續鑄(zhu)(zhu)造(zao)(zao),之后(hou)進行(xing)(xing)冷(leng)(leng)軋(ya)或冷(leng)(leng)加(jia)(jia)工(gong),生(sheng)產(chan)的無氧(yang)銅(tong)(tong)桿為(wei)鑄(zhu)(zhu)造(zao)(zao)組織(zhi),含(han)氧(yang)量一(yi)般在(zai)(zai)20ppm以下。由于(yu)制造(zao)(zao)工(gong)藝的不(bu)同,所以在(zai)(zai)組織(zhi)結構、氧(yang)含(han)量分布、雜質的形式及分布等諸多方(fang)面(mian)有較大差(cha)別。
一、拉制性能
銅桿的(de)(de)拉制性能跟很多因(yin)素有關,如雜質的(de)(de)含量(liang)、氧含量(liang)及分布、工(gong)藝控制等。下面分別從以(yi)上幾個方(fang)面對銅桿的(de)(de)拉制性能進行(xing)分析。
1、熔化方式(shi)對S等雜質的影(ying)響
連鑄(zhu)連軋(ya)生(sheng)產銅桿主(zhu)要(yao)是通過氣(qi)體(ti)的(de)燃燒使銅桿熔(rong)化,在燃燒的(de)過程中(zhong),通過氧化和揮發作用,可(ke)一(yi)(yi)定程度減少部(bu)分雜質進入(ru)銅液(ye),因此連鑄(zhu)連軋(ya)法對原料要(yao)求相對低一(yi)(yi)些。上(shang)引連鑄(zhu)生(sheng)產無(wu)氧銅桿,由于是用感應電(dian)爐熔(rong)化,電(dian)解(jie)銅表面的(de)“銅綠”“銅豆”基(ji)本都熔(rong)入(ru)到銅液(ye)中(zhong)。其中(zhong)熔(rong)入(ru)的(de)S對無(wu)氧銅桿塑性影響極(ji)大,會增加拉(la)絲斷線率。
2、鑄造(zao)過程中雜質的進入
在生產(chan)(chan)過(guo)(guo)(guo)程(cheng)中(zhong),連鑄(zhu)連軋工(gong)藝需通(tong)過(guo)(guo)(guo)保溫爐、溜槽、中(zhong)間包(bao)轉運銅液,相(xiang)對容(rong)易(yi)造成(cheng)(cheng)耐火(huo)材料的(de)(de)(de)剝落,在軋制過(guo)(guo)(guo)程(cheng)中(zhong)需要通(tong)過(guo)(guo)(guo)軋輥,造成(cheng)(cheng)鐵質的(de)(de)(de)脫(tuo)落,會(hui)(hui)給銅桿造成(cheng)(cheng)外(wai)部夾雜。而熱(re)軋中(zhong)皮上(shang)和皮下氧化物的(de)(de)(de)軋入,會(hui)(hui)給低氧桿的(de)(de)(de)拉絲造成(cheng)(cheng)不利的(de)(de)(de)影響。上(shang)引連鑄(zhu)法生產(chan)(chan)工(gong)藝流程(cheng)較(jiao)短,銅液是通(tong)過(guo)(guo)(guo)聯體爐內(nei)潛流式完成(cheng)(cheng),對耐火(huo)材料的(de)(de)(de)沖(chong)擊不大(da),結晶是通(tong)過(guo)(guo)(guo)石墨(mo)模內(nei)進(jin)行,所以過(guo)(guo)(guo)程(cheng)中(zhong)可能產(chan)(chan)生的(de)(de)(de)污染源較(jiao)少(shao),雜質進(jin)入的(de)(de)(de)機會(hui)(hui)較(jiao)少(shao)。
O、S、P是與銅(tong)(tong)會生產化合物的(de)元素(su)。在(zai)(zai)熔態銅(tong)(tong)中,氧可以溶解一(yi)部(bu)分(fen),但(dan)當銅(tong)(tong)冷(leng)凝(ning)時,氧幾乎不溶解于銅(tong)(tong)中。熔態時所溶解的(de)氧,以銅(tong)(tong)=氧化亞(ya)銅(tong)(tong)共(gong)晶(jing)體(ti)析出(chu),分(fen)布在(zai)(zai)晶(jing)粒(li)晶(jing)界處。銅(tong)(tong)-氧化亞(ya)銅(tong)(tong)共(gong)晶(jing)體(ti)的(de)出(chu)現(xian),顯著降低了銅(tong)(tong)的(de)塑性(xing)。
硫(liu)可以(yi)溶解在(zai)熔體的銅中,但在(zai)室溫下,其溶解度幾乎降(jiang)低(di)到零,它(ta)以(yi)硫(liu)化亞銅的形(xing)式出現在(zai)晶(jing)粒晶(jing)界處,會(hui)顯(xian)著降(jiang)低(di)銅的塑性。
3、氧在低(di)氧銅(tong)桿(gan)和無(wu)氧銅(tong)桿(gan)中分布形式及其(qi)影響
氧含量對(dui)低氧銅(tong)(tong)桿(gan)的(de)拉線(xian)(xian)性(xing)能(neng)有(you)著(zhu)明顯(xian)的(de)影響(xiang)。當氧含量增加到(dao)最(zui)佳值時,銅(tong)(tong)桿(gan)的(de)斷(duan)線(xian)(xian)率最(zui)低。這是因為氧在與大(da)部分雜質反應的(de)過程中都起到(dao)了清除器的(de)作(zuo)用。適度(du)的(de)氧還有(you)利于去(qu)除銅(tong)(tong)液(ye)中的(de)氫,生成(cheng)(cheng)水蒸(zheng)氣溢(yi)出,減(jian)少氣孔的(de)形成(cheng)(cheng)。最(zui)佳的(de)氧含量為拉線(xian)(xian)工藝提供了最(zui)好(hao)的(de)條件。
低氧銅(tong)桿氧化(hua)物(wu)(wu)的(de)分布(bu):在連續澆鑄中凝固的(de)最初階段,散熱速率和均勻(yun)冷卻(que)是決定銅(tong)桿氧化(hua)物(wu)(wu)分布(bu)的(de)主要因素。不均勻(yun)冷卻(que)會引起銅(tong)桿內部結構本質(zhi)上(shang)的(de)差(cha)異,但后續的(de)熱加工,柱狀晶通常會遭到破壞,使(shi)氧化(hua)亞銅(tong)顆粒細微化(hua)和均勻(yun)分布(bu)。氧化(hua)物(wu)(wu)顆粒聚集(ji)(ji)而(er)(er)產(chan)生(sheng)的(de)典型情況是中心爆裂(lie)。除氧化(hua)物(wu)(wu)顆粒分布(bu)的(de)影響外,具有(you)較(jiao)(jiao)小氧化(hua)物(wu)(wu)顆粒的(de)銅(tong)桿顯示出較(jiao)(jiao)好的(de)拉線特(te)性,較(jiao)(jiao)大(da)的(de)Cu2O顆粒容(rong)易造(zao)成應力集(ji)(ji)中點而(er)(er)斷裂(lie)。
無(wu)氧(yang)(yang)(yang)銅含氧(yang)(yang)(yang)量超(chao)標(biao),銅桿(gan)變脆(cui)(cui),延(yan)伸率(lv)下(xia)(xia)降,拉伸式(shi)樣端(duan)口(kou)顯暗紅色,結晶組織(zhi)疏松(song)。當(dang)氧(yang)(yang)(yang)含量超(chao)出8ppm時,工藝(yi)性(xing)能變差,表現為鑄造(zao)及拉伸過程中斷桿(gan)及斷線(xian)率(lv)極(ji)具增高。這是由于氧(yang)(yang)(yang)能與(yu)銅生成氧(yang)(yang)(yang)化亞(ya)銅脆(cui)(cui)性(xing)相(xiang),形成銅-氧(yang)(yang)(yang)化亞(ya)銅共晶體(ti),以(yi)網狀組織(zhi)分布在(zai)境界上(shang)。這種脆(cui)(cui)性(xing)相(xiang)硬(ying)度高,在(zai)冷變形時將會與(yu)銅機(ji)體(ti)脫(tuo)離(li),導致銅桿(gan)的機(ji)械性(xing)能下(xia)(xia)降,在(zai)后(hou)續加工中容易造(zao)成斷裂現象。氧(yang)(yang)(yang)含量高還能導致無(wu)氧(yang)(yang)(yang)銅桿(gan)導電率(lv)下(xia)(xia)降。因此,必須嚴格控制上(shang)引(yin)連鑄工藝(yi)及產品質量。
4、氫的影響
在上引連(lian)鑄中,氧含量控制較(jiao)低(di),氧化物的副作用(yong)唄(bai)**降低(di),但氫的影響成為較(jiao)顯著的問題。吸氣后熔體(ti)中存在平(ping)衡反應:H2O(g)=[O]+2[H];
氣(qi)(qi)體(ti)及疏(shu)松(song)(song)是(shi)在(zai)結(jie)(jie)晶(jing)(jing)(jing)(jing)的(de)過(guo)(guo)(guo)程(cheng)中(zhong),氫(qing)從過(guo)(guo)(guo)飽和的(de)溶液(ye)(ye)中(zhong)析(xi)出并聚集(ji)而(er)形(xing)成(cheng)(cheng)的(de)。在(zai)結(jie)(jie)晶(jing)(jing)(jing)(jing)前析(xi)出的(de)氫(qing)又可還原氧化亞銅而(er)生成(cheng)(cheng)水氣(qi)(qi)泡。由于(yu)上引鑄造的(de)特點是(shi)銅液(ye)(ye)自上而(er)下(xia)的(de)結(jie)(jie)晶(jing)(jing)(jing)(jing),形(xing)成(cheng)(cheng)的(de)液(ye)(ye)**形(xing)狀近似錐型(xing)。銅液(ye)(ye)結(jie)(jie)晶(jing)(jing)(jing)(jing)前析(xi)出的(de)氣(qi)(qi)體(ti)在(zai)上浮過(guo)(guo)(guo)程(cheng)中(zhong)被堵在(zai)凝固(gu)組織內,結(jie)(jie)晶(jing)(jing)(jing)(jing)時(shi)(shi)在(zai)鑄桿內形(xing)成(cheng)(cheng)氣(qi)(qi)孔(kong)。上引的(de)含(han)氣(qi)(qi)量少(shao)時(shi)(shi),析(xi)出的(de)氫(qing)存在(zai)于(yu)晶(jing)(jing)(jing)(jing)界處(chu),形(xing)成(cheng)(cheng)疏(shu)松(song)(song);含(han)氣(qi)(qi)量多(duo)時(shi)(shi),則(ze)聚集(ji)成(cheng)(cheng)氣(qi)(qi)孔(kong),因此,氣(qi)(qi)孔(kong)和疏(shu)松(song)(song)是(shi)氫(qing)氣(qi)(qi)和水蒸氣(qi)(qi)兩(liang)者形(xing)成(cheng)(cheng)的(de)。
氫來(lai)源(yuan)于上引(yin)生產(chan)過(guo)程(cheng)中(zhong)的(de)各個工(gong)藝環節,如原料(liao)電(dian)解銅(tong)的(de)“銅(tong)綠”、輔料(liao)木炭**、氣候環境**、石墨結晶器未干(gan)燥等。因(yin)此,熔化爐中(zhong)的(de)銅(tong)液表(biao)面應覆蓋經烘烤的(de)木炭,電(dian)解銅(tong)應盡量去除“銅(tong)綠”、“銅(tong)豆”“耳朵”,對提高(gao)無氧銅(tong)桿質(zhi)量非常重要。
在連(lian)鑄(zhu)連(lian)軋工藝(yi)中,往(wang)(wang)往(wang)(wang)采用適度控制(zhi)氧含量來控制(zhi)氫。Cu2O+ H2= 2Cu+ H2O
由(you)于銅液(ye)在鑄造過程中(zhong)是自(zi)下而上結晶,銅液(ye)中(zhong)的(de)氧和氫所產生的(de)水(shui)蒸氣很容易上浮(fu)跑出,銅液(ye)中(zhong)的(de)氫大部分(fen)能(neng)被有效(xiao)去除(chu),因而對銅桿的(de)影響(xiang)較小。
二、表面質量
在生產電磁線等產品的(de)過程中(zhong),對銅(tong)(tong)(tong)桿的(de)表面質量(liang)(liang)也需提出要求。需要拉制后的(de)銅(tong)(tong)(tong)絲表面無(wu)毛(mao)刺、銅(tong)(tong)(tong)粉(fen)少、無(wu)油污。并通過扭(niu)轉試(shi)驗測量(liang)(liang)表面銅(tong)(tong)(tong)粉(fen)的(de)質量(liang)(liang)和扭(niu)轉后觀察(cha)銅(tong)(tong)(tong)桿的(de)復原情況來(lai)判(pan)定其好壞(huai)。
在(zai)連鑄(zhu)(zhu)連軋(ya)過(guo)(guo)程中(zhong),從(cong)鑄(zhu)(zhu)造(zao)(zao)到軋(ya)制(zhi)前,溫度(du)高,完全暴露于(yu)空氣(qi)中(zhong),使鑄(zhu)(zhu)坯表面(mian)形成(cheng)較厚的氧化層,在(zai)軋(ya)制(zhi)過(guo)(guo)程中(zhong),隨著軋(ya)輥的轉(zhuan)動,氧化物顆粒軋(ya)入(ru)銅(tong)線表面(mian)。由于(yu)氧化亞銅(tong)是(shi)高熔點脆性化合物,對(dui)于(yu)軋(ya)入(ru)較深的氧化亞銅(tong),當成(cheng)條(tiao)狀的聚集(ji)物遇模具拉伸時,就(jiu)會是(shi)銅(tong)桿外(wai)表面(mian)產生毛刺,給后續的涂(tu)漆造(zao)(zao)成(cheng)麻(ma)煩。
而上引連鑄工藝制造的(de)無(wu)氧(yang)(yang)銅(tong)桿,由于鑄造和冷卻完全與氧(yang)(yang)隔絕,后(hou)續亦無(wu)熱軋過程,銅(tong)桿表面(mian)無(wu)軋入表面(mian)的(de)氧(yang)(yang)化(hua)物,質(zhi)量較好,拉制后(hou)銅(tong)粉(fen)少(shao),上述(shu)問題較少(shao)存在。
無氧(yang)銅桿(gan)也分進(jin)口設(she)備(bei)(bei)做(zuo)的和國產(chan)設(she)備(bei)(bei)做(zuo)的,但目前進(jin)口產(chan)品已無明顯優勢,銅桿(gan)產(chan)品出來后區別不是很大,只要銅板(ban)選的好(hao),生(sheng)產(chan)控制比較穩定,國產(chan)設(she)備(bei)(bei)也能產(chan)出可(ke)拉(la)伸0.05的銅桿(gan).進(jin)口設(she)備(bei)(bei)一(yi)般是芬(fen)蘭奧托昆普的設(she)備(bei)(bei),國產(chan)設(she)備(bei)(bei)最好(hao)的應該是上海的海軍(jun)廠的了(le),生(sheng)產(chan)時間最長,軍(jun)工(gong)企業,質量可(ke)靠。
低(di)氧銅桿進口設備(bei)(bei)國際主要有(you)兩種(zhong)(zhong),一種(zhong)(zhong)是(shi)(shi)美國南(nan)線設備(bei)(bei),英文(wen)是(shi)(shi)SOUTHWIRE,國內廠家是(shi)(shi)南(nan)京華新(xin),江(jiang)西(xi)銅業,另一種(zhong)(zhong)是(shi)(shi)德國CONTIROD設備(bei)(bei),國內廠家是(shi)(shi)常(chang)州金源(yuan),天(tian)津大無縫。
無(wu)(wu)氧(yang)(yang)及低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)從含氧(yang)(yang)量(liang)上(shang)容易區別,無(wu)(wu)氧(yang)(yang)銅是(shi)含氧(yang)(yang)量(liang)在(zai)(zai)10-20個PPM以(yi)下(xia),但(dan)(dan)(dan)目(mu)前(qian)(qian)有(you)(you)的(de)廠家只能做(zuo)到50個PPM以(yi)下(xia).低(di)氧(yang)(yang)銅桿(gan)(gan)(gan)(gan)在(zai)(zai) 200-400個PPM,好(hao)的(de)桿(gan)(gan)(gan)(gan)子一般含氧(yang)(yang)量(liang)控制(zhi)在(zai)(zai)250個PPM左右,無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)(gan)一般采取(qu)的(de)是(shi)上(shang)引法,低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)是(shi)連鑄連軋,兩(liang)種產品相對(dui)而言低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)對(dui)漆(qi)包線(xian)性(xing) 能更適應些,如(ru)柔軟性(xing),回彈角,繞線(xian)性(xing)能.但(dan)(dan)(dan)低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)對(dui)拉絲條件相對(dui)要苛刻些,同樣(yang)拉伸(shen)0.2的(de)細絲,如(ru)果伸(shen)線(xian)條件不(bu)好(hao),普通的(de)無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)(gan)可拉而好(hao)的(de)低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)就(jiu)斷 線(xian),但(dan)(dan)(dan)如(ru)果放(fang)在(zai)(zai)好(hao)的(de)伸(shen)線(xian)條件,同樣(yang)的(de)桿(gan)(gan)(gan)(gan)子,低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)說(shuo)不(bu)定就(jiu)能拉到雙(shuang)零五,而普通無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)(gan)最多(duo)只能拉伸(shen)到0.1而已(yi),當(dang)然(ran)做(zuo)的(de)最細的(de)如(ru)雙(shuang)零二卻非(fei)得依靠(kao)進口的(de) 無(wu)(wu)氧(yang)(yang)銅桿(gan)(gan)(gan)(gan)了.目(mu)前(qian)(qian)有(you)(you)企業嘗試用剝皮的(de)方(fang)式來處理(li)低(di)氧(yang)(yang)桿(gan)(gan)(gan)(gan)來伸(shen)0.03線(xian).但(dan)(dan)(dan)有(you)(you)關這方(fang)面的(de)內容我還不(bu)是(shi)很清楚。
音響線一般反而喜歡用無(wu)氧桿,這和無(wu)氧桿是單晶(jing)銅,低(di)氧桿是多晶(jing)銅有關(guan)。
氧(yang)銅(tong)桿(gan)和無氧(yang)銅(tong)桿(gan)由于制造方法的不同,致使(shi)存在差別,具有各(ge)自的特點。
一、關于氧的吸(xi)入和脫去以及它的存在狀態(tai)
生產銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)陰極銅(tong)(tong)(tong)的(de)(de)(de)含(han)氧(yang)(yang)(yang)(yang)量(liang)一般(ban)在(zai)10—50ppm,在(zai)常(chang)溫下(xia)氧(yang)(yang)(yang)(yang)在(zai)銅(tong)(tong)(tong)中的(de)(de)(de)固(gu)溶(rong)度約2ppm。低(di)(di)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)含(han)氧(yang)(yang)(yang)(yang)量(liang)一般(ban)在(zai)200(175)—400(450)ppm,因此氧(yang)(yang)(yang)(yang)的(de)(de)(de)進入是(shi)(shi)在(zai)銅(tong)(tong)(tong)的(de)(de)(de)液態(tai)(tai)下(xia)吸(xi)入的(de)(de)(de),而上引法(fa)無(wu)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則相(xiang)(xiang)(xiang)反,氧(yang)(yang)(yang)(yang)在(zai)液態(tai)(tai)銅(tong)(tong)(tong)下(xia)保(bao)持相(xiang)(xiang)(xiang)當時(shi)間后,被還原而脫(tuo)去,通常(chang)這(zhe)種桿(gan)(gan)的(de)(de)(de)含(han)氧(yang)(yang)(yang)(yang)量(liang)都在(zai)10—50ppm以下(xia),最低(di)(di)可達1-2ppm,從(cong)組織上看,低(di)(di)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)(de)氧(yang)(yang)(yang)(yang),以氧(yang)(yang)(yang)(yang)化(hua)銅(tong)(tong)(tong)狀態(tai)(tai),存在(zai)于晶(jing)(jing)粒(li)邊界附近,這(zhe)對(dui)低(di)(di)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)而言可以說是(shi)(shi)常(chang)見(jian)的(de)(de)(de)但對(dui)無(wu)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則很少見(jian)。氧(yang)(yang)(yang)(yang)化(hua)銅(tong)(tong)(tong)以夾雜形式在(zai)晶(jing)(jing)界出現對(dui)材(cai)料的(de)(de)(de)韌性產生負面影響。而無(wu)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)(de)氧(yang)(yang)(yang)(yang)很低(di)(di),所(suo)以這(zhe)種銅(tong)(tong)(tong)的(de)(de)(de)組織是(shi)(shi)均勻的(de)(de)(de)單(dan)相(xiang)(xiang)(xiang)組織對(dui)韌性有(you)利。在(zai)無(wu)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)中的(de)(de)(de)多孔性是(shi)(shi)不常(chang)見(jian)的(de)(de)(de),而在(zai)低(di)(di)氧(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)中則是(shi)(shi)常(chang)見(jian)的(de)(de)(de)一種缺(que)陷。
二(er)、熱軋組織和鑄造(zao)組織的(de)區別
低氧(yang)銅(tong)桿(gan)(gan)(gan)由于經過熱(re)軋,所(suo)以其組織(zhi)(zhi)(zhi)屬(shu)熱(re)加工組織(zhi)(zhi)(zhi),原來的(de)(de)鑄(zhu)造組織(zhi)(zhi)(zhi)已經破(po)碎,在8mm的(de)(de)桿(gan)(gan)(gan)時已有(you)(you)再結晶(jing)的(de)(de)形(xing)式出現,而無(wu)氧(yang)銅(tong)桿(gan)(gan)(gan)屬(shu)鑄(zhu)造組織(zhi)(zhi)(zhi),晶(jing)粒粗(cu)大(da),這(zhe)是(shi)(shi)為什么,無(wu)氧(yang)銅(tong)的(de)(de)再結晶(jing)溫(wen)度較高(gao)(gao),需(xu)要(yao)較高(gao)(gao)退火溫(wen)度的(de)(de)固有(you)(you)原因(yin)。這(zhe)是(shi)(shi)因(yin)為,再結晶(jing)發(fa)生在晶(jing)粒邊(bian)界附(fu)近,無(wu)氧(yang)銅(tong)桿(gan)(gan)(gan)組織(zhi)(zhi)(zhi)晶(jing)粒粗(cu)大(da),晶(jing)粒尺(chi)寸甚至能達幾個(ge)毫(hao)米,因(yin)而晶(jing)粒邊(bian)界少(shao),即使(shi)通(tong)過拉制(zhi)(zhi)變形(xing),但晶(jing)粒邊(bian)界相(xiang)對低氧(yang)銅(tong)桿(gan)(gan)(gan)還是(shi)(shi)較少(shao),所(suo)以需(xu)要(yao)較高(gao)(gao)的(de)(de)退火功(gong)(gong)率。對無(wu)氧(yang)銅(tong)成功(gong)(gong)的(de)(de)退火要(yao)求是(shi)(shi):由桿(gan)(gan)(gan)經拉制(zhi)(zhi),但尚未鑄(zhu)造組織(zhi)(zhi)(zhi)的(de)(de)線時的(de)(de)第一次(ci)退火,其退火功(gong)(gong)率應比同(tong)樣(yang)情況的(de)(de)低氧(yang)銅(tong)高(gao)(gao)10——15%。經繼續拉制(zhi)(zhi),在以后階段(duan)的(de)(de)退火功(gong)(gong)率應留(liu)有(you)(you)足(zu)夠的(de)(de)余量和對低氧(yang)銅(tong)和無(wu)氧(yang)銅(tong)切(qie)實區別執行(xing)不同(tong)的(de)(de)退火工藝,以保證在制(zhi)(zhi)品(pin)和成品(pin)導線的(de)(de)柔軟性。
三、夾雜(za),氧(yang)含量波動,表面(mian)氧(yang)化物(wu)和(he)可能(neng)存在的熱軋(ya)缺陷的差別
無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan)的(de)(de)(de)可(ke)拉(la)(la)性(xing)在(zai)(zai)所有(you)線徑里(li)與(yu)低氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan)相(xiang)比都是優越的(de)(de)(de),除(chu)上述組織原因外,無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan)夾(jia)雜(za)少,含氧(yang)(yang)(yang)量穩定,無(wu)(wu)熱(re)軋可(ke)能產生(sheng)的(de)(de)(de)缺陷,桿(gan)(gan)表氧(yang)(yang)(yang)化(hua)物(wu)(wu)厚度可(ke)達(da)≤15A。在(zai)(zai)連鑄連軋生(sheng)產過程中如果(guo)工藝不(bu)穩定,對(dui)氧(yang)(yang)(yang)監控不(bu)嚴,含氧(yang)(yang)(yang)量不(bu)穩定將直(zhi)接影響(xiang)桿(gan)(gan)的(de)(de)(de)性(xing)能。如果(guo)桿(gan)(gan)的(de)(de)(de)表面氧(yang)(yang)(yang)化(hua)物(wu)(wu)能在(zai)(zai)后工序(xu)的(de)(de)(de)連續清洗中得(de)以(yi)彌補(bu)外,但(dan)比較麻(ma)煩的(de)(de)(de)是有(you)相(xiang)當多的(de)(de)(de)氧(yang)(yang)(yang)化(hua)物(wu)(wu)存在(zai)(zai)于“皮下”,對(dui)拉(la)(la)線斷(duan)線影響(xiang)更直(zhi)接,故(gu)而在(zai)(zai)拉(la)(la)制微(wei)(wei)細線,超微(wei)(wei)細線時(shi),為(wei)了減少斷(duan)線,有(you)時(shi)要對(dui)銅(tong)(tong)桿(gan)(gan)采取不(bu)得(de)已的(de)(de)(de)辦法——剝(bo)(bo)皮,甚至二次(ci)剝(bo)(bo)皮的(de)(de)(de)原因所在(zai)(zai),目(mu)的(de)(de)(de)要除(chu)去皮下氧(yang)(yang)(yang)化(hua)物(wu)(wu)。
四、低氧銅桿(gan)和(he)無氧銅桿(gan)的(de)韌性有差別
兩者都(dou)可以拉到0.015mm,但在低(di)溫超導(dao)線中的(de)低(di)溫級無氧銅(tong),其細絲間的(de)間距(ju)只有0.001mm.
五、從(cong)制(zhi)桿的(de)原材料到制(zhi)線的(de)經(jing)濟性有差別。
制(zhi)造無(wu)氧(yang)銅桿(gan)(gan)要求(qiu)質量較(jiao)高的(de)(de)原(yuan)材料。一般,拉制(zhi)直(zhi)徑(jing)>1mm的(de)(de)銅線時(shi),低氧(yang)銅桿(gan)(gan)的(de)(de)優點比較(jiao)明顯,而無(wu)氧(yang)銅桿(gan)(gan)顯得更為優越的(de)(de)是(shi)拉制(zhi)直(zhi)徑(jing)<0.5mm的(de)(de)銅線。
六、低氧(yang)銅(tong)桿的制線工藝(yi)與(yu)無(wu)氧(yang)銅(tong)桿的有所不(bu)同。
低氧(yang)銅(tong)(tong)(tong)(tong)桿(gan)的(de)制(zhi)線(xian)(xian)(xian)(xian)工(gong)藝(yi)(yi)(yi)不(bu)能照搬(ban)到無(wu)氧(yang)銅(tong)(tong)(tong)(tong)桿(gan)的(de)制(zhi)線(xian)(xian)(xian)(xian)工(gong)藝(yi)(yi)(yi)上(shang)來,至少兩者的(de)退(tui)火工(gong)藝(yi)(yi)(yi)是不(bu)同的(de)。因為線(xian)(xian)(xian)(xian)的(de)柔軟(ruan)(ruan)性(xing)深受材料成(cheng)份(fen)和制(zhi)桿(gan),制(zhi)線(xian)(xian)(xian)(xian)和退(tui)火工(gong)藝(yi)(yi)(yi)的(de)影(ying)響,不(bu)能簡單地說低氧(yang)銅(tong)(tong)(tong)(tong)或無(wu)氧(yang)銅(tong)(tong)(tong)(tong)誰軟(ruan)(ruan)誰硬。