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來源:行(xing)業動(dong)態 閱讀(du):109292 發布時間:2019-07-05
導(dao)讀:由于生(sheng)產銅桿(gan)的(de)兩者的(de)工(gong)藝(yi)不同,所生(sheng)產的(de)銅桿(gan)中的(de)含氧(yang)量(liang)及外觀就不同。上引生(sheng)產的(de)銅桿(gan),工(gong)藝(yi)得當氧(yang)含量(liang)在(zai)10ppm以下,叫(jiao)無(wu)氧(yang)銅桿(gan);連鑄(zhu)連鑄(zhu)生(sheng)產的(de)銅桿(gan) 是在(zai)保護條(tiao)件下的(de)熱軋(ya),氧(yang)含量(liang)在(zai)200-500ppm范圍內,但有時也(ye)高達(da)700ppm以上,一般情況下,此種方法生(sheng)產的(de)銅外表光亮,低氧(yang)銅桿(gan),有時也(ye)叫(jiao)光桿(gan)。
銅桿(gan)是電纜行(xing)(xing)業(ye)的(de)主要原料,生產(chan)的(de)方式(shi)(shi)主要有(you)兩(liang)種——連(lian)(lian)(lian)鑄連(lian)(lian)(lian)軋法(fa)和上引(yin)(yin)連(lian)(lian)(lian)鑄法(fa)。連(lian)(lian)(lian)鑄連(lian)(lian)(lian)軋低氧(yang)(yang)銅桿(gan)的(de)生產(chan)方法(fa)較多(duo),其(qi)特點是金屬在豎爐(lu)中融化(hua)后(hou)(hou),銅液通過保(bao)溫爐(lu)、溜槽(cao)、中間(jian)包,從(cong)澆管進入封閉的(de)模腔(qiang)內(nei),采(cai)用較大(da)的(de)冷(leng)(leng)卻(que)強度(du)進行(xing)(xing)冷(leng)(leng)卻(que),形成鑄坯,然后(hou)(hou)進行(xing)(xing)多(duo)道次軋制,生產(chan)的(de)低氧(yang)(yang)銅桿(gan)為(wei)熱加(jia)工(gong)(gong)組(zu)織(zhi),原來的(de)鑄造(zao)組(zu)織(zhi)已經破碎,含(han)氧(yang)(yang)量一(yi)(yi)般為(wei)200~400ppm之(zhi)(zhi)間(jian)。無(wu)氧(yang)(yang)銅桿(gan)國內(nei)基本全部(bu)采(cai)用上引(yin)(yin)連(lian)(lian)(lian)鑄法(fa)生產(chan),金屬在感(gan)應電爐(lu)中融化(hua)后(hou)(hou)通過石(shi)墨(mo)模進行(xing)(xing)上引(yin)(yin)連(lian)(lian)(lian)續(xu)鑄造(zao),之(zhi)(zhi)后(hou)(hou)進行(xing)(xing)冷(leng)(leng)軋或(huo)冷(leng)(leng)加(jia)工(gong)(gong),生產(chan)的(de)無(wu)氧(yang)(yang)銅桿(gan)為(wei)鑄造(zao)組(zu)織(zhi),含(han)氧(yang)(yang)量一(yi)(yi)般在20ppm以(yi)下。由于制造(zao)工(gong)(gong)藝的(de)不同,所以(yi)在組(zu)織(zhi)結(jie)構(gou)、氧(yang)(yang)含(han)量分布、雜質的(de)形式(shi)(shi)及分布等諸多(duo)方面有(you)較大(da)差(cha)別。
一、拉制性能
銅桿的(de)(de)拉(la)(la)制(zhi)性能跟很(hen)多因素有關(guan),如雜質(zhi)的(de)(de)含量(liang)、氧含量(liang)及(ji)分布、工(gong)藝控制(zhi)等。下面分別從(cong)以上(shang)幾個方面對(dui)銅桿的(de)(de)拉(la)(la)制(zhi)性能進行分析(xi)。
1、熔化(hua)方式對S等雜質(zhi)的影響
連鑄(zhu)連軋生產(chan)銅桿主(zhu)要(yao)是通過氣體的燃(ran)燒使銅桿熔化,在燃(ran)燒的過程中(zhong),通過氧化和揮發(fa)作用(yong),可一定(ding)程度減少部分雜質(zhi)進入銅液(ye),因此連鑄(zhu)連軋法對(dui)原料(liao)要(yao)求相對(dui)低一些。上引連鑄(zhu)生產(chan)無(wu)氧銅桿,由(you)于是用(yong)感應(ying)電(dian)爐熔化,電(dian)解銅表面的“銅綠”“銅豆”基(ji)本都熔入到銅液(ye)中(zhong)。其(qi)中(zhong)熔入的S對(dui)無(wu)氧銅桿塑性影響極(ji)大,會增加拉絲斷線率。
2、鑄造過程中雜質的進入
在(zai)生產(chan)過(guo)(guo)(guo)程(cheng)中(zhong)(zhong)(zhong),連(lian)鑄連(lian)軋(ya)(ya)(ya)工藝(yi)需(xu)通(tong)過(guo)(guo)(guo)保(bao)溫爐(lu)(lu)、溜槽(cao)、中(zhong)(zhong)(zhong)間包轉運(yun)銅液(ye)(ye),相對容易造(zao)成(cheng)耐火(huo)(huo)材料(liao)的(de)剝落(luo),在(zai)軋(ya)(ya)(ya)制(zhi)過(guo)(guo)(guo)程(cheng)中(zhong)(zhong)(zhong)需(xu)要(yao)通(tong)過(guo)(guo)(guo)軋(ya)(ya)(ya)輥,造(zao)成(cheng)鐵質的(de)脫落(luo),會(hui)給銅桿造(zao)成(cheng)外部夾雜(za)。而熱軋(ya)(ya)(ya)中(zhong)(zhong)(zhong)皮上和皮下氧(yang)化物的(de)軋(ya)(ya)(ya)入,會(hui)給低氧(yang)桿的(de)拉絲造(zao)成(cheng)不利的(de)影響。上引連(lian)鑄法生產(chan)工藝(yi)流程(cheng)較(jiao)短,銅液(ye)(ye)是通(tong)過(guo)(guo)(guo)聯體爐(lu)(lu)內(nei)潛流式完成(cheng),對耐火(huo)(huo)材料(liao)的(de)沖擊(ji)不大(da),結晶是通(tong)過(guo)(guo)(guo)石(shi)墨模內(nei)進行(xing),所以過(guo)(guo)(guo)程(cheng)中(zhong)(zhong)(zhong)可(ke)能(neng)產(chan)生的(de)污染源較(jiao)少,雜(za)質進入的(de)機會(hui)較(jiao)少。
O、S、P是與(yu)銅(tong)會生產(chan)化合物的元(yuan)素。在熔態銅(tong)中(zhong),氧可以(yi)溶(rong)解一部分,但當銅(tong)冷(leng)凝時,氧幾(ji)乎不溶(rong)解于(yu)銅(tong)中(zhong)。熔態時所(suo)溶(rong)解的氧,以(yi)銅(tong)=氧化亞(ya)銅(tong)共晶(jing)體析出,分布(bu)在晶(jing)粒(li)晶(jing)界(jie)處。銅(tong)-氧化亞(ya)銅(tong)共晶(jing)體的出現,顯著降低(di)了銅(tong)的塑(su)性(xing)。
硫(liu)可(ke)以(yi)溶解在(zai)熔體的銅中,但在(zai)室溫下,其(qi)溶解度幾乎(hu)降(jiang)低到零,它以(yi)硫(liu)化亞銅的形式(shi)出現在(zai)晶粒晶界處,會(hui)顯著降(jiang)低銅的塑性。
3、氧在低氧銅(tong)桿和(he)無氧銅(tong)桿中分(fen)布(bu)形(xing)式及(ji)其影響
氧含量對低(di)氧銅桿的(de)拉(la)線(xian)(xian)性(xing)能有著(zhu)明顯的(de)影(ying)響。當(dang)氧含量增加到(dao)最佳(jia)值時(shi),銅桿的(de)斷線(xian)(xian)率最低(di)。這(zhe)是因為(wei)氧在與大部分雜(za)質反(fan)應的(de)過程中都起(qi)到(dao)了(le)清(qing)除器的(de)作用。適度的(de)氧還有利(li)于(yu)去除銅液中的(de)氫,生(sheng)成(cheng)(cheng)水蒸氣溢出,減少(shao)氣孔(kong)的(de)形成(cheng)(cheng)。最佳(jia)的(de)氧含量為(wei)拉(la)線(xian)(xian)工藝提供了(le)最好的(de)條件。
低氧(yang)(yang)銅(tong)桿氧(yang)(yang)化(hua)物(wu)的分(fen)(fen)布:在連續澆(jiao)鑄中(zhong)凝固的最初(chu)階段,散(san)熱(re)速率和均(jun)勻(yun)冷卻(que)(que)是決定銅(tong)桿氧(yang)(yang)化(hua)物(wu)分(fen)(fen)布的主要因素。不均(jun)勻(yun)冷卻(que)(que)會(hui)引起銅(tong)桿內部(bu)結構本質上的差異,但后續的熱(re)加(jia)工,柱狀晶通常會(hui)遭到破壞(huai),使氧(yang)(yang)化(hua)亞銅(tong)顆粒(li)(li)細微化(hua)和均(jun)勻(yun)分(fen)(fen)布。氧(yang)(yang)化(hua)物(wu)顆粒(li)(li)聚集而(er)產(chan)生的典型情況是中(zhong)心爆裂。除(chu)氧(yang)(yang)化(hua)物(wu)顆粒(li)(li)分(fen)(fen)布的影響外,具有較小氧(yang)(yang)化(hua)物(wu)顆粒(li)(li)的銅(tong)桿顯(xian)示出較好的拉線(xian)特性,較大的Cu2O顆粒(li)(li)容(rong)易造成應力集中(zhong)點而(er)斷裂。
無氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)含氧(yang)(yang)(yang)(yang)(yang)量超(chao)標,銅(tong)(tong)桿(gan)(gan)變脆(cui),延伸率下(xia)降(jiang),拉(la)伸式樣端口(kou)顯暗(an)紅(hong)色,結晶(jing)組織疏(shu)松。當氧(yang)(yang)(yang)(yang)(yang)含量超(chao)出8ppm時,工(gong)(gong)藝性能(neng)變差,表現為(wei)鑄造(zao)及(ji)拉(la)伸過程中斷(duan)桿(gan)(gan)及(ji)斷(duan)線率極具增高(gao)。這是由于氧(yang)(yang)(yang)(yang)(yang)能(neng)與銅(tong)(tong)生(sheng)成(cheng)氧(yang)(yang)(yang)(yang)(yang)化亞(ya)銅(tong)(tong)脆(cui)性相,形成(cheng)銅(tong)(tong)-氧(yang)(yang)(yang)(yang)(yang)化亞(ya)銅(tong)(tong)共(gong)晶(jing)體,以網(wang)狀(zhuang)組織分(fen)布(bu)在境界上。這種脆(cui)性相硬度高(gao),在冷(leng)變形時將會(hui)與銅(tong)(tong)機體脫離,導致銅(tong)(tong)桿(gan)(gan)的(de)機械性能(neng)下(xia)降(jiang),在后續(xu)加工(gong)(gong)中容(rong)易造(zao)成(cheng)斷(duan)裂現象。氧(yang)(yang)(yang)(yang)(yang)含量高(gao)還(huan)能(neng)導致無氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan)導電率下(xia)降(jiang)。因(yin)此,必須嚴格控制上引(yin)連鑄工(gong)(gong)藝及(ji)產品質(zhi)量。
4、氫的影響
在上引連鑄中,氧含量控制較低,氧化物(wu)的副作用唄**降低,但氫的影響成為較顯著的問題。吸(xi)氣后熔體中存在平衡反應(ying):H2O(g)=[O]+2[H];
氣(qi)(qi)體及疏(shu)松是(shi)在結(jie)(jie)(jie)晶的過(guo)程中(zhong),氫從過(guo)飽和的溶液(ye)(ye)中(zhong)析(xi)出(chu)(chu)并聚(ju)(ju)集而形(xing)(xing)成(cheng)的。在結(jie)(jie)(jie)晶前析(xi)出(chu)(chu)的氫又可還原氧(yang)化亞銅而生成(cheng)水氣(qi)(qi)泡。由于上(shang)引鑄(zhu)造的特點是(shi)銅液(ye)(ye)自(zi)上(shang)而下的結(jie)(jie)(jie)晶,形(xing)(xing)成(cheng)的液(ye)(ye)**形(xing)(xing)狀近(jin)似錐型。銅液(ye)(ye)結(jie)(jie)(jie)晶前析(xi)出(chu)(chu)的氣(qi)(qi)體在上(shang)浮(fu)過(guo)程中(zhong)被堵(du)在凝(ning)固組(zu)織內,結(jie)(jie)(jie)晶時在鑄(zhu)桿內形(xing)(xing)成(cheng)氣(qi)(qi)孔。上(shang)引的含氣(qi)(qi)量少時,析(xi)出(chu)(chu)的氫存在于晶界處(chu),形(xing)(xing)成(cheng)疏(shu)松;含氣(qi)(qi)量多時,則聚(ju)(ju)集成(cheng)氣(qi)(qi)孔,因此,氣(qi)(qi)孔和疏(shu)松是(shi)氫氣(qi)(qi)和水蒸氣(qi)(qi)兩者(zhe)形(xing)(xing)成(cheng)的。
氫來源于上引(yin)生產(chan)過程中(zhong)的(de)各個工藝環(huan)節,如原料電解銅(tong)的(de)“銅(tong)綠”、輔料木(mu)炭(tan)**、氣候環(huan)境**、石墨結(jie)晶器未干燥等(deng)。因此,熔化爐中(zhong)的(de)銅(tong)液表面(mian)應(ying)(ying)覆蓋經烘烤的(de)木(mu)炭(tan),電解銅(tong)應(ying)(ying)盡量去(qu)除“銅(tong)綠”、“銅(tong)豆”“耳朵”,對提高無氧銅(tong)桿質(zhi)量非常(chang)重(zhong)要(yao)。
在連鑄連軋工藝中,往往采用適(shi)度控制(zhi)氧含量來(lai)控制(zhi)氫(qing)。Cu2O+ H2= 2Cu+ H2O
由(you)于銅(tong)液在鑄(zhu)造過程中是(shi)自下而(er)上結晶,銅(tong)液中的氧(yang)和氫(qing)所產(chan)生的水蒸氣很容易上浮跑(pao)出,銅(tong)液中的氫(qing)大部(bu)分能被有效去(qu)除(chu),因而(er)對銅(tong)桿的影響(xiang)較小。
二、表面質量
在生產(chan)電磁線(xian)等(deng)產(chan)品(pin)的(de)過(guo)程中(zhong),對銅(tong)桿的(de)表面(mian)質量也需(xu)提(ti)出要(yao)求(qiu)。需(xu)要(yao)拉制(zhi)后(hou)的(de)銅(tong)絲表面(mian)無(wu)毛刺、銅(tong)粉(fen)少、無(wu)油污。并通過(guo)扭轉試驗(yan)測量表面(mian)銅(tong)粉(fen)的(de)質量和扭轉后(hou)觀察銅(tong)桿的(de)復原情況來判定其(qi)好(hao)壞。
在連鑄(zhu)連軋(ya)過(guo)程(cheng)中,從鑄(zhu)造到軋(ya)制前,溫度高,完全暴露于(yu)空氣中,使鑄(zhu)坯表面形成(cheng)較厚的(de)(de)氧(yang)化層(ceng),在軋(ya)制過(guo)程(cheng)中,隨著軋(ya)輥(gun)的(de)(de)轉動(dong),氧(yang)化物顆粒軋(ya)入(ru)銅(tong)(tong)線表面。由于(yu)氧(yang)化亞銅(tong)(tong)是(shi)高熔(rong)點脆(cui)性化合物,對于(yu)軋(ya)入(ru)較深的(de)(de)氧(yang)化亞銅(tong)(tong),當成(cheng)條狀的(de)(de)聚集物遇(yu)模具(ju)拉伸時,就會是(shi)銅(tong)(tong)桿外表面產(chan)生毛刺,給后續的(de)(de)涂(tu)漆造成(cheng)麻煩。
而(er)上引連鑄工藝制造的無氧銅桿(gan),由(you)于鑄造和(he)冷卻完全與氧隔(ge)絕(jue),后續亦(yi)無熱(re)軋過程,銅桿(gan)表(biao)面無軋入表(biao)面的氧化物,質量較好(hao),拉制后銅粉少,上述問題較少存(cun)在。
無氧銅桿也分(fen)進(jin)(jin)口設備(bei)做的(de)(de)和國(guo)產(chan)(chan)(chan)設備(bei)做的(de)(de),但目前(qian)進(jin)(jin)口產(chan)(chan)(chan)品已無明(ming)顯優勢,銅桿產(chan)(chan)(chan)品出來后區(qu)別不是很大,只要(yao)銅板選的(de)(de)好,生產(chan)(chan)(chan)控(kong)制比(bi)較穩(wen)定,國(guo)產(chan)(chan)(chan)設備(bei)也能產(chan)(chan)(chan)出可(ke)拉伸0.05的(de)(de)銅桿.進(jin)(jin)口設備(bei)一般是芬(fen)蘭奧托昆普(pu)的(de)(de)設備(bei),國(guo)產(chan)(chan)(chan)設備(bei)最好的(de)(de)應該是上海的(de)(de)海軍(jun)廠(chang)的(de)(de)了(le),生產(chan)(chan)(chan)時間最長,軍(jun)工(gong)企業,質量(liang)可(ke)靠。
低(di)氧銅(tong)桿進口設(she)備(bei)國(guo)(guo)際主(zhu)要有兩(liang)種(zhong),一(yi)種(zhong)是(shi)(shi)美國(guo)(guo)南(nan)線設(she)備(bei),英文是(shi)(shi)SOUTHWIRE,國(guo)(guo)內廠家是(shi)(shi)南(nan)京華新,江(jiang)西銅(tong)業,另一(yi)種(zhong)是(shi)(shi)德國(guo)(guo)CONTIROD設(she)備(bei),國(guo)(guo)內廠家是(shi)(shi)常(chang)州金源,天津大無縫。
無(wu)氧(yang)(yang)(yang)(yang)及低(di)氧(yang)(yang)(yang)(yang)桿(gan)從含氧(yang)(yang)(yang)(yang)量上(shang)容(rong)易區(qu)別(bie),無(wu)氧(yang)(yang)(yang)(yang)銅(tong)是(shi)含氧(yang)(yang)(yang)(yang)量在(zai)10-20個(ge)(ge)PPM以下(xia)(xia),但(dan)(dan)目前有的(de)(de)(de)廠家只能做到50個(ge)(ge)PPM以下(xia)(xia).低(di)氧(yang)(yang)(yang)(yang)銅(tong)桿(gan)在(zai) 200-400個(ge)(ge)PPM,好(hao)的(de)(de)(de)桿(gan)子(zi)一(yi)般含氧(yang)(yang)(yang)(yang)量控制(zhi)在(zai)250個(ge)(ge)PPM左右,無(wu)氧(yang)(yang)(yang)(yang)桿(gan)一(yi)般采(cai)取的(de)(de)(de)是(shi)上(shang)引法(fa),低(di)氧(yang)(yang)(yang)(yang)桿(gan)是(shi)連鑄連軋,兩種產品(pin)相對而言低(di)氧(yang)(yang)(yang)(yang)桿(gan)對漆包線(xian)(xian)(xian)性 能更(geng)適應(ying)些(xie),如(ru)柔軟性,回彈角,繞(rao)線(xian)(xian)(xian)性能.但(dan)(dan)低(di)氧(yang)(yang)(yang)(yang)桿(gan)對拉(la)絲(si)條(tiao)件(jian)相對要苛刻些(xie),同樣拉(la)伸(shen)0.2的(de)(de)(de)細絲(si),如(ru)果伸(shen)線(xian)(xian)(xian)條(tiao)件(jian)不好(hao),普(pu)通的(de)(de)(de)無(wu)氧(yang)(yang)(yang)(yang)桿(gan)可拉(la)而好(hao)的(de)(de)(de)低(di)氧(yang)(yang)(yang)(yang)桿(gan)就(jiu)斷 線(xian)(xian)(xian),但(dan)(dan)如(ru)果放(fang)在(zai)好(hao)的(de)(de)(de)伸(shen)線(xian)(xian)(xian)條(tiao)件(jian),同樣的(de)(de)(de)桿(gan)子(zi),低(di)氧(yang)(yang)(yang)(yang)桿(gan)說不定就(jiu)能拉(la)到雙零五(wu),而普(pu)通無(wu)氧(yang)(yang)(yang)(yang)桿(gan)最多(duo)只能拉(la)伸(shen)到0.1而已,當然做的(de)(de)(de)最細的(de)(de)(de)如(ru)雙零二卻(que)非得(de)依靠進口的(de)(de)(de) 無(wu)氧(yang)(yang)(yang)(yang)銅(tong)桿(gan)了(le).目前有企業嘗(chang)試用剝皮的(de)(de)(de)方式來處理低(di)氧(yang)(yang)(yang)(yang)桿(gan)來伸(shen)0.03線(xian)(xian)(xian).但(dan)(dan)有關(guan)這(zhe)方面的(de)(de)(de)內容(rong)我還(huan)不是(shi)很清楚。
音響(xiang)線(xian)一般反(fan)而喜(xi)歡用(yong)無(wu)氧桿(gan),這和(he)無(wu)氧桿(gan)是單(dan)晶(jing)銅(tong),低氧桿(gan)是多晶(jing)銅(tong)有關。
氧銅(tong)桿(gan)和無氧銅(tong)桿(gan)由于制造方法的不同,致(zhi)使存(cun)在差(cha)別,具有各自的特(te)點(dian)。
一(yi)、關于氧的(de)吸入和脫去以及它的(de)存在(zai)狀(zhuang)態
生(sheng)產銅(tong)(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)(de)陰(yin)極銅(tong)(tong)(tong)(tong)的(de)(de)(de)(de)含(han)氧(yang)(yang)量一般(ban)在(zai)(zai)10—50ppm,在(zai)(zai)常(chang)(chang)溫下氧(yang)(yang)在(zai)(zai)銅(tong)(tong)(tong)(tong)中(zhong)的(de)(de)(de)(de)固溶度約2ppm。低氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)(de)含(han)氧(yang)(yang)量一般(ban)在(zai)(zai)200(175)—400(450)ppm,因此氧(yang)(yang)的(de)(de)(de)(de)進入是(shi)在(zai)(zai)銅(tong)(tong)(tong)(tong)的(de)(de)(de)(de)液態(tai)(tai)下吸入的(de)(de)(de)(de),而上(shang)引(yin)法無(wu)(wu)氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)則相(xiang)反,氧(yang)(yang)在(zai)(zai)液態(tai)(tai)銅(tong)(tong)(tong)(tong)下保持相(xiang)當時間后,被還原而脫去,通常(chang)(chang)這種桿(gan)(gan)的(de)(de)(de)(de)含(han)氧(yang)(yang)量都在(zai)(zai)10—50ppm以下,最(zui)低可(ke)達(da)1-2ppm,從組織上(shang)看(kan),低氧(yang)(yang)銅(tong)(tong)(tong)(tong)中(zhong)的(de)(de)(de)(de)氧(yang)(yang),以氧(yang)(yang)化(hua)銅(tong)(tong)(tong)(tong)狀態(tai)(tai),存在(zai)(zai)于晶粒邊界附近(jin),這對(dui)低氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)而言可(ke)以說(shuo)是(shi)常(chang)(chang)見的(de)(de)(de)(de)但(dan)對(dui)無(wu)(wu)氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)則很少見。氧(yang)(yang)化(hua)銅(tong)(tong)(tong)(tong)以夾雜(za)形式在(zai)(zai)晶界出現對(dui)材料(liao)的(de)(de)(de)(de)韌性(xing)產生(sheng)負面影(ying)響。而無(wu)(wu)氧(yang)(yang)銅(tong)(tong)(tong)(tong)中(zhong)的(de)(de)(de)(de)氧(yang)(yang)很低,所以這種銅(tong)(tong)(tong)(tong)的(de)(de)(de)(de)組織是(shi)均勻的(de)(de)(de)(de)單相(xiang)組織對(dui)韌性(xing)有利。在(zai)(zai)無(wu)(wu)氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)中(zhong)的(de)(de)(de)(de)多孔性(xing)是(shi)不常(chang)(chang)見的(de)(de)(de)(de),而在(zai)(zai)低氧(yang)(yang)銅(tong)(tong)(tong)(tong)桿(gan)(gan)中(zhong)則是(shi)常(chang)(chang)見的(de)(de)(de)(de)一種缺陷。
二(er)、熱軋組(zu)織和(he)鑄造組(zu)織的區別
低氧銅(tong)(tong)桿(gan)由于經過熱軋,所以其(qi)組(zu)(zu)織(zhi)屬熱加工組(zu)(zu)織(zhi),原(yuan)來(lai)的(de)(de)(de)(de)鑄造(zao)組(zu)(zu)織(zhi)已經破碎,在8mm的(de)(de)(de)(de)桿(gan)時已有(you)再(zai)結晶(jing)(jing)的(de)(de)(de)(de)形(xing)式出現,而無(wu)氧銅(tong)(tong)桿(gan)屬鑄造(zao)組(zu)(zu)織(zhi),晶(jing)(jing)粒粗大,這是(shi)(shi)為什么,無(wu)氧銅(tong)(tong)的(de)(de)(de)(de)再(zai)結晶(jing)(jing)溫度(du)較高(gao),需要較高(gao)退(tui)(tui)(tui)火(huo)(huo)溫度(du)的(de)(de)(de)(de)固(gu)有(you)原(yuan)因(yin)。這是(shi)(shi)因(yin)為,再(zai)結晶(jing)(jing)發生在晶(jing)(jing)粒邊界附(fu)近,無(wu)氧銅(tong)(tong)桿(gan)組(zu)(zu)織(zhi)晶(jing)(jing)粒粗大,晶(jing)(jing)粒尺寸甚至(zhi)能達幾個(ge)毫米,因(yin)而晶(jing)(jing)粒邊界少,即使通過拉制(zhi)變(bian)形(xing),但(dan)(dan)晶(jing)(jing)粒邊界相對低氧銅(tong)(tong)桿(gan)還(huan)是(shi)(shi)較少,所以需要較高(gao)的(de)(de)(de)(de)退(tui)(tui)(tui)火(huo)(huo)功(gong)(gong)率(lv)。對無(wu)氧銅(tong)(tong)成功(gong)(gong)的(de)(de)(de)(de)退(tui)(tui)(tui)火(huo)(huo)要求是(shi)(shi):由桿(gan)經拉制(zhi),但(dan)(dan)尚未鑄造(zao)組(zu)(zu)織(zhi)的(de)(de)(de)(de)線時的(de)(de)(de)(de)第(di)一(yi)次(ci)退(tui)(tui)(tui)火(huo)(huo),其(qi)退(tui)(tui)(tui)火(huo)(huo)功(gong)(gong)率(lv)應(ying)比同樣情況的(de)(de)(de)(de)低氧銅(tong)(tong)高(gao)10——15%。經繼續(xu)拉制(zhi),在以后(hou)階段的(de)(de)(de)(de)退(tui)(tui)(tui)火(huo)(huo)功(gong)(gong)率(lv)應(ying)留有(you)足夠的(de)(de)(de)(de)余量和對低氧銅(tong)(tong)和無(wu)氧銅(tong)(tong)切實區別執行不同的(de)(de)(de)(de)退(tui)(tui)(tui)火(huo)(huo)工藝(yi),以保證在制(zhi)品和成品導線的(de)(de)(de)(de)柔軟性。
三、夾雜,氧含量(liang)波動,表(biao)面氧化物和可能存在的熱軋(ya)缺陷(xian)的差別
無(wu)氧(yang)(yang)銅(tong)桿的(de)(de)(de)可拉(la)性在(zai)所有(you)(you)線(xian)徑里與低氧(yang)(yang)銅(tong)桿相(xiang)比都是優越(yue)的(de)(de)(de),除上述組織原(yuan)因(yin)外(wai),無(wu)氧(yang)(yang)銅(tong)桿夾雜少,含(han)氧(yang)(yang)量(liang)(liang)穩定,無(wu)熱軋(ya)可能產生的(de)(de)(de)缺陷,桿表氧(yang)(yang)化物厚度可達≤15A。在(zai)連鑄連軋(ya)生產過程中如(ru)果工藝不穩定,對(dui)氧(yang)(yang)監控不嚴,含(han)氧(yang)(yang)量(liang)(liang)不穩定將直(zhi)接影響桿的(de)(de)(de)性能。如(ru)果桿的(de)(de)(de)表面氧(yang)(yang)化物能在(zai)后工序(xu)的(de)(de)(de)連續清洗中得以彌(mi)補外(wai),但比較麻(ma)煩的(de)(de)(de)是有(you)(you)相(xiang)當多的(de)(de)(de)氧(yang)(yang)化物存在(zai)于“皮下(xia)(xia)”,對(dui)拉(la)線(xian)斷線(xian)影響更直(zhi)接,故而在(zai)拉(la)制微(wei)細線(xian),超微(wei)細線(xian)時(shi),為了減少斷線(xian),有(you)(you)時(shi)要(yao)(yao)對(dui)銅(tong)桿采取(qu)不得已(yi)的(de)(de)(de)辦(ban)法——剝皮,甚至二次剝皮的(de)(de)(de)原(yuan)因(yin)所在(zai),目(mu)的(de)(de)(de)要(yao)(yao)除去皮下(xia)(xia)氧(yang)(yang)化物。
四、低氧銅(tong)桿(gan)和(he)無(wu)氧銅(tong)桿(gan)的韌(ren)性有差別
兩者都可(ke)以拉到0.015mm,但在低溫超導線中的(de)低溫級無氧銅,其細絲(si)間(jian)的(de)間(jian)距只有0.001mm.
五、從(cong)制桿的原材料到制線的經濟性有(you)差別(bie)。
制造無氧銅桿(gan)要求(qiu)質量較高(gao)的(de)原材料。一(yi)般,拉制直徑>1mm的(de)銅線時,低氧銅桿(gan)的(de)優點(dian)比較明顯,而無氧銅桿(gan)顯得(de)更為優越的(de)是拉制直徑<0.5mm的(de)銅線。
六、低氧(yang)銅桿的(de)制線工(gong)藝與無氧(yang)銅桿的(de)有(you)所不(bu)同。
低(di)氧銅(tong)(tong)桿的制線工藝不(bu)能(neng)照搬到無(wu)氧銅(tong)(tong)桿的制線工藝上來,至少(shao)兩者(zhe)的退(tui)火工藝是(shi)不(bu)同的。因為線的柔軟性深受(shou)材料(liao)成份和制桿,制線和退(tui)火工藝的影響,不(bu)能(neng)簡單地說低(di)氧銅(tong)(tong)或無(wu)氧銅(tong)(tong)誰軟誰硬。
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