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來(lai)源(yuan):行(xing)業(ye)動態 閱(yue)讀:109602 發(fa)布(bu)時間:2019-07-05
導讀:由于(yu)生(sheng)產銅(tong)桿的(de)兩者的(de)工藝不(bu)同(tong),所(suo)生(sheng)產的(de)銅(tong)桿中的(de)含(han)(han)氧(yang)(yang)(yang)量及外(wai)觀就不(bu)同(tong)。上引生(sheng)產的(de)銅(tong)桿,工藝得當(dang)氧(yang)(yang)(yang)含(han)(han)量在10ppm以(yi)下,叫無氧(yang)(yang)(yang)銅(tong)桿;連鑄連鑄生(sheng)產的(de)銅(tong)桿 是在保護條件下的(de)熱(re)軋,氧(yang)(yang)(yang)含(han)(han)量在200-500ppm范(fan)圍(wei)內,但有(you)時(shi)也高達700ppm以(yi)上,一般(ban)情況下,此種方(fang)法(fa)生(sheng)產的(de)銅(tong)外(wai)表(biao)光亮,低氧(yang)(yang)(yang)銅(tong)桿,有(you)時(shi)也叫光桿。
銅(tong)(tong)(tong)桿是電纜(lan)行業的(de)主要原料,生產(chan)(chan)的(de)方(fang)式(shi)主要有兩種——連鑄(zhu)連軋(ya)法(fa)和上引(yin)(yin)連鑄(zhu)法(fa)。連鑄(zhu)連軋(ya)低(di)氧(yang)(yang)銅(tong)(tong)(tong)桿的(de)生產(chan)(chan)方(fang)法(fa)較(jiao)多(duo)(duo),其特點是金(jin)屬在豎爐(lu)中(zhong)融化(hua)后,銅(tong)(tong)(tong)液通(tong)過保溫(wen)爐(lu)、溜槽(cao)、中(zhong)間(jian)(jian)包,從(cong)澆管進入封閉的(de)模腔內(nei),采用(yong)較(jiao)大的(de)冷卻強(qiang)度進行冷卻,形成鑄(zhu)坯,然后進行多(duo)(duo)道次軋(ya)制,生產(chan)(chan)的(de)低(di)氧(yang)(yang)銅(tong)(tong)(tong)桿為(wei)(wei)熱加工組(zu)織(zhi),原來的(de)鑄(zhu)造(zao)(zao)組(zu)織(zhi)已經(jing)破碎(sui),含氧(yang)(yang)量一般(ban)為(wei)(wei)200~400ppm之(zhi)間(jian)(jian)。無氧(yang)(yang)銅(tong)(tong)(tong)桿國(guo)內(nei)基(ji)本(ben)全部采用(yong)上引(yin)(yin)連鑄(zhu)法(fa)生產(chan)(chan),金(jin)屬在感應電爐(lu)中(zhong)融化(hua)后通(tong)過石墨模進行上引(yin)(yin)連續鑄(zhu)造(zao)(zao),之(zhi)后進行冷軋(ya)或冷加工,生產(chan)(chan)的(de)無氧(yang)(yang)銅(tong)(tong)(tong)桿為(wei)(wei)鑄(zhu)造(zao)(zao)組(zu)織(zhi),含氧(yang)(yang)量一般(ban)在20ppm以下。由于制造(zao)(zao)工藝的(de)不同(tong),所以在組(zu)織(zhi)結構、氧(yang)(yang)含量分布、雜質的(de)形式(shi)及分布等諸多(duo)(duo)方(fang)面有較(jiao)大差(cha)別。
一、拉制性能
銅(tong)桿(gan)的拉(la)制性(xing)能(neng)跟很多(duo)因(yin)素有關,如雜(za)質的含(han)量、氧含(han)量及分(fen)(fen)布、工藝(yi)控制等(deng)。下面分(fen)(fen)別從以(yi)上幾個方(fang)面對銅(tong)桿(gan)的拉(la)制性(xing)能(neng)進行分(fen)(fen)析(xi)。
1、熔化方式對S等雜質(zhi)的(de)影響
連(lian)鑄(zhu)連(lian)軋生(sheng)產銅(tong)(tong)(tong)桿主要(yao)是通(tong)過氣體的燃燒(shao)使銅(tong)(tong)(tong)桿熔(rong)化,在燃燒(shao)的過程(cheng)中(zhong)(zhong),通(tong)過氧(yang)(yang)化和揮(hui)發(fa)作(zuo)用,可一(yi)定程(cheng)度減少部分(fen)雜質進入銅(tong)(tong)(tong)液,因此連(lian)鑄(zhu)連(lian)軋法(fa)對原料要(yao)求相對低一(yi)些(xie)。上引連(lian)鑄(zhu)生(sheng)產無(wu)氧(yang)(yang)銅(tong)(tong)(tong)桿,由于是用感應電爐熔(rong)化,電解銅(tong)(tong)(tong)表面的“銅(tong)(tong)(tong)綠”“銅(tong)(tong)(tong)豆”基(ji)本都熔(rong)入到銅(tong)(tong)(tong)液中(zhong)(zhong)。其(qi)中(zhong)(zhong)熔(rong)入的S對無(wu)氧(yang)(yang)銅(tong)(tong)(tong)桿塑性(xing)影響(xiang)極大,會增加拉絲斷線率。
2、鑄(zhu)造(zao)過程中雜質(zhi)的進入
在生(sheng)產過(guo)程中,連鑄連軋工(gong)藝需通過(guo)保溫爐、溜槽(cao)、中間包(bao)轉運銅(tong)液,相對(dui)容易造(zao)(zao)成(cheng)耐火材料(liao)的(de)(de)(de)剝落,在軋制過(guo)程中需要(yao)通過(guo)軋輥,造(zao)(zao)成(cheng)鐵質(zhi)的(de)(de)(de)脫落,會給銅(tong)桿造(zao)(zao)成(cheng)外(wai)部(bu)夾(jia)雜(za)。而熱軋中皮上和皮下氧(yang)化(hua)物的(de)(de)(de)軋入,會給低氧(yang)桿的(de)(de)(de)拉絲造(zao)(zao)成(cheng)不利的(de)(de)(de)影響。上引連鑄法(fa)生(sheng)產工(gong)藝流程較短(duan),銅(tong)液是(shi)通過(guo)聯體爐內潛流式完成(cheng),對(dui)耐火材料(liao)的(de)(de)(de)沖擊(ji)不大(da),結晶是(shi)通過(guo)石(shi)墨(mo)模內進(jin)行,所以過(guo)程中可能(neng)產生(sheng)的(de)(de)(de)污染(ran)源較少,雜(za)質(zhi)進(jin)入的(de)(de)(de)機會較少。
O、S、P是與(yu)銅(tong)(tong)(tong)會(hui)生產化合物的元素。在(zai)熔態(tai)銅(tong)(tong)(tong)中(zhong),氧(yang)可以(yi)溶解一部分,但當銅(tong)(tong)(tong)冷(leng)凝時,氧(yang)幾乎(hu)不溶解于銅(tong)(tong)(tong)中(zhong)。熔態(tai)時所溶解的氧(yang),以(yi)銅(tong)(tong)(tong)=氧(yang)化亞銅(tong)(tong)(tong)共(gong)(gong)晶體析出,分布在(zai)晶粒晶界處(chu)。銅(tong)(tong)(tong)-氧(yang)化亞銅(tong)(tong)(tong)共(gong)(gong)晶體的出現,顯著降低了銅(tong)(tong)(tong)的塑性。
硫可以溶(rong)解在熔(rong)體的銅(tong)中,但在室(shi)溫下,其溶(rong)解度幾乎降低到零,它以硫化(hua)亞銅(tong)的形式(shi)出現在晶(jing)粒(li)晶(jing)界(jie)處,會顯著(zhu)降低銅(tong)的塑性(xing)。
3、氧(yang)在低氧(yang)銅桿(gan)(gan)和無氧(yang)銅桿(gan)(gan)中(zhong)分布(bu)形式及其(qi)影響
氧(yang)含(han)量(liang)(liang)對低氧(yang)銅桿(gan)(gan)的(de)(de)(de)拉線(xian)性能有著明顯(xian)的(de)(de)(de)影(ying)響。當氧(yang)含(han)量(liang)(liang)增加到(dao)最(zui)佳(jia)值時(shi),銅桿(gan)(gan)的(de)(de)(de)斷線(xian)率最(zui)低。這是因為(wei)氧(yang)在與大部分雜質反應的(de)(de)(de)過程中(zhong)都起(qi)到(dao)了清除器的(de)(de)(de)作用。適度的(de)(de)(de)氧(yang)還有利于去除銅液中(zhong)的(de)(de)(de)氫,生成水(shui)蒸氣溢出,減少(shao)氣孔的(de)(de)(de)形(xing)成。最(zui)佳(jia)的(de)(de)(de)氧(yang)含(han)量(liang)(liang)為(wei)拉線(xian)工藝提供了最(zui)好的(de)(de)(de)條件。
低氧銅(tong)桿(gan)氧化(hua)物(wu)(wu)的(de)(de)分布(bu)(bu):在連(lian)續澆鑄(zhu)中(zhong)凝固的(de)(de)最初階段,散(san)熱速率(lv)和均勻冷卻是決定銅(tong)桿(gan)氧化(hua)物(wu)(wu)分布(bu)(bu)的(de)(de)主要因素(su)。不均勻冷卻會引起(qi)銅(tong)桿(gan)內(nei)部結構本質上(shang)的(de)(de)差(cha)異,但后續的(de)(de)熱加工,柱狀晶(jing)通常會遭(zao)到破壞,使(shi)氧化(hua)亞(ya)銅(tong)顆(ke)(ke)粒(li)(li)(li)細微化(hua)和均勻分布(bu)(bu)。氧化(hua)物(wu)(wu)顆(ke)(ke)粒(li)(li)(li)聚集(ji)而(er)產(chan)生(sheng)的(de)(de)典型情(qing)況是中(zhong)心(xin)爆裂。除氧化(hua)物(wu)(wu)顆(ke)(ke)粒(li)(li)(li)分布(bu)(bu)的(de)(de)影(ying)響外(wai),具(ju)有較(jiao)小(xiao)氧化(hua)物(wu)(wu)顆(ke)(ke)粒(li)(li)(li)的(de)(de)銅(tong)桿(gan)顯(xian)示(shi)出(chu)較(jiao)好(hao)的(de)(de)拉線特性,較(jiao)大的(de)(de)Cu2O顆(ke)(ke)粒(li)(li)(li)容易造成應(ying)力集(ji)中(zhong)點而(er)斷(duan)裂。
無氧(yang)(yang)(yang)銅(tong)(tong)含(han)氧(yang)(yang)(yang)量超(chao)標,銅(tong)(tong)桿(gan)(gan)變脆,延(yan)伸(shen)率下降(jiang),拉伸(shen)式樣端口顯暗紅色(se),結晶(jing)組織疏松(song)。當(dang)氧(yang)(yang)(yang)含(han)量超(chao)出(chu)8ppm時(shi),工藝(yi)性能變差,表現(xian)為鑄造及(ji)拉伸(shen)過(guo)程中(zhong)斷(duan)桿(gan)(gan)及(ji)斷(duan)線率極(ji)具增高。這是由于氧(yang)(yang)(yang)能與銅(tong)(tong)生成(cheng)氧(yang)(yang)(yang)化亞銅(tong)(tong)脆性相,形(xing)成(cheng)銅(tong)(tong)-氧(yang)(yang)(yang)化亞銅(tong)(tong)共晶(jing)體,以網(wang)狀組織分布在(zai)境界上(shang)。這種(zhong)脆性相硬(ying)度高,在(zai)冷變形(xing)時(shi)將會與銅(tong)(tong)機體脫離,導(dao)(dao)致(zhi)銅(tong)(tong)桿(gan)(gan)的機械性能下降(jiang),在(zai)后續加工中(zhong)容易(yi)造成(cheng)斷(duan)裂現(xian)象。氧(yang)(yang)(yang)含(han)量高還能導(dao)(dao)致(zhi)無氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan)導(dao)(dao)電(dian)率下降(jiang)。因此,必須嚴格控制上(shang)引(yin)連鑄工藝(yi)及(ji)產品(pin)質(zhi)量。
4、氫的影響
在(zai)上(shang)引連鑄中(zhong),氧含量控制(zhi)較(jiao)低(di),氧化物的副作用唄**降低(di),但氫(qing)的影響成為較(jiao)顯著的問題。吸氣后熔體中(zhong)存在(zai)平衡反應(ying):H2O(g)=[O]+2[H];
氣體(ti)及疏(shu)松是在(zai)結晶(jing)(jing)的(de)過(guo)程中(zhong),氫(qing)從過(guo)飽(bao)和的(de)溶(rong)液(ye)中(zhong)析(xi)(xi)出(chu)并聚集而(er)形(xing)成(cheng)(cheng)(cheng)的(de)。在(zai)結晶(jing)(jing)前析(xi)(xi)出(chu)的(de)氫(qing)又(you)可還原氧(yang)化亞銅而(er)生成(cheng)(cheng)(cheng)水氣泡。由(you)于(yu)上(shang)(shang)引鑄造(zao)的(de)特(te)點是銅液(ye)自上(shang)(shang)而(er)下(xia)的(de)結晶(jing)(jing),形(xing)成(cheng)(cheng)(cheng)的(de)液(ye)**形(xing)狀近似錐型(xing)。銅液(ye)結晶(jing)(jing)前析(xi)(xi)出(chu)的(de)氣體(ti)在(zai)上(shang)(shang)浮過(guo)程中(zhong)被(bei)堵在(zai)凝(ning)固(gu)組織內,結晶(jing)(jing)時在(zai)鑄桿(gan)內形(xing)成(cheng)(cheng)(cheng)氣孔(kong)。上(shang)(shang)引的(de)含氣量少時,析(xi)(xi)出(chu)的(de)氫(qing)存(cun)在(zai)于(yu)晶(jing)(jing)界(jie)處(chu),形(xing)成(cheng)(cheng)(cheng)疏(shu)松;含氣量多(duo)時,則聚集成(cheng)(cheng)(cheng)氣孔(kong),因此,氣孔(kong)和疏(shu)松是氫(qing)氣和水蒸氣兩者形(xing)成(cheng)(cheng)(cheng)的(de)。
氫來源于上引生產過程(cheng)中的各個工藝環節,如原料電(dian)解銅(tong)(tong)的“銅(tong)(tong)綠”、輔料木炭**、氣候環境**、石墨結晶器未干燥(zao)等(deng)。因此(ci),熔化爐(lu)中的銅(tong)(tong)液表面應覆蓋經烘烤的木炭,電(dian)解銅(tong)(tong)應盡量去除“銅(tong)(tong)綠”、“銅(tong)(tong)豆”“耳朵(duo)”,對(dui)提高無(wu)氧(yang)銅(tong)(tong)桿(gan)質量非(fei)常(chang)重要。
在連鑄連軋(ya)工藝中,往(wang)往(wang)采用適度控制氧(yang)含量來控制氫。Cu2O+ H2= 2Cu+ H2O
由于銅液在鑄(zhu)造過程中(zhong)是(shi)自下而(er)上(shang)結晶,銅液中(zhong)的氧和氫所產生的水蒸氣很容(rong)易上(shang)浮跑出,銅液中(zhong)的氫大部(bu)分能(neng)被有(you)效去除(chu),因而(er)對銅桿的影響較小。
二、表面質量
在生產電磁線等產品的過程中,對(dui)銅桿的表面質(zhi)量(liang)也需(xu)提(ti)出(chu)要(yao)求(qiu)。需(xu)要(yao)拉制(zhi)后的銅絲表面無毛刺、銅粉少(shao)、無油污(wu)。并通過扭轉試驗測量(liang)表面銅粉的質(zhi)量(liang)和扭轉后觀察銅桿的復原情況來判定其好(hao)壞。
在連鑄連軋(ya)過(guo)程中,從鑄造到軋(ya)制前,溫度高,完全暴露(lu)于(yu)(yu)空氣(qi)中,使(shi)鑄坯(pi)表面形成較厚的氧化(hua)層,在軋(ya)制過(guo)程中,隨著軋(ya)輥的轉(zhuan)動(dong),氧化(hua)物(wu)(wu)顆粒軋(ya)入銅線(xian)表面。由(you)于(yu)(yu)氧化(hua)亞(ya)銅是高熔(rong)點(dian)脆性化(hua)合(he)物(wu)(wu),對于(yu)(yu)軋(ya)入較深的氧化(hua)亞(ya)銅,當成條(tiao)狀(zhuang)的聚集物(wu)(wu)遇(yu)模(mo)具拉伸(shen)時(shi),就會是銅桿外表面產生毛刺,給(gei)后續的涂漆造成麻(ma)煩(fan)。
而(er)上引連(lian)鑄(zhu)(zhu)工藝制(zhi)造的無(wu)氧銅(tong)(tong)桿,由于鑄(zhu)(zhu)造和冷(leng)卻(que)完(wan)全(quan)與氧隔絕(jue),后(hou)續亦無(wu)熱(re)軋過程,銅(tong)(tong)桿表(biao)面無(wu)軋入表(biao)面的氧化物,質量較好,拉制(zhi)后(hou)銅(tong)(tong)粉少,上述(shu)問題較少存在。
無(wu)氧銅(tong)(tong)(tong)桿(gan)也(ye)分進口設(she)(she)備(bei)做的(de)(de)和(he)國(guo)產(chan)設(she)(she)備(bei)做的(de)(de),但(dan)目前進口產(chan)品已無(wu)明顯優勢,銅(tong)(tong)(tong)桿(gan)產(chan)品出(chu)(chu)來后區別不是很大,只(zhi)要銅(tong)(tong)(tong)板選的(de)(de)好(hao),生產(chan)控(kong)制比較穩定,國(guo)產(chan)設(she)(she)備(bei)也(ye)能(neng)產(chan)出(chu)(chu)可拉伸0.05的(de)(de)銅(tong)(tong)(tong)桿(gan).進口設(she)(she)備(bei)一般(ban)是芬蘭奧托昆普的(de)(de)設(she)(she)備(bei),國(guo)產(chan)設(she)(she)備(bei)最好(hao)的(de)(de)應該是上(shang)海的(de)(de)海軍(jun)廠的(de)(de)了(le),生產(chan)時間(jian)最長,軍(jun)工企業,質(zhi)量可靠。
低氧銅桿進口設備(bei)(bei)國(guo)際主(zhu)要(yao)有(you)兩種,一種是美國(guo)南線設備(bei)(bei),英(ying)文是SOUTHWIRE,國(guo)內(nei)廠家是南京華新,江西銅業,另一種是德國(guo)CONTIROD設備(bei)(bei),國(guo)內(nei)廠家是常州金源,天(tian)津大(da)無縫。
無(wu)氧(yang)及低(di)氧(yang)桿(gan)(gan)(gan)從含氧(yang)量上容(rong)易區別,無(wu)氧(yang)銅是(shi)含氧(yang)量在(zai)10-20個PPM以(yi)下,但(dan)(dan)目(mu)前有(you)的(de)(de)廠(chang)家只能(neng)做(zuo)(zuo)到50個PPM以(yi)下.低(di)氧(yang)銅桿(gan)(gan)(gan)在(zai) 200-400個PPM,好(hao)的(de)(de)桿(gan)(gan)(gan)子一般(ban)含氧(yang)量控制在(zai)250個PPM左(zuo)右,無(wu)氧(yang)桿(gan)(gan)(gan)一般(ban)采取的(de)(de)是(shi)上引法,低(di)氧(yang)桿(gan)(gan)(gan)是(shi)連鑄(zhu)連軋,兩種產品相對(dui)而(er)言低(di)氧(yang)桿(gan)(gan)(gan)對(dui)漆包線(xian)性(xing) 能(neng)更適應(ying)些(xie),如柔軟(ruan)性(xing),回彈角,繞線(xian)性(xing)能(neng).但(dan)(dan)低(di)氧(yang)桿(gan)(gan)(gan)對(dui)拉絲條件相對(dui)要(yao)苛刻(ke)些(xie),同(tong)樣拉伸(shen)(shen)(shen)0.2的(de)(de)細(xi)絲,如果伸(shen)(shen)(shen)線(xian)條件不好(hao),普通的(de)(de)無(wu)氧(yang)桿(gan)(gan)(gan)可(ke)拉而(er)好(hao)的(de)(de)低(di)氧(yang)桿(gan)(gan)(gan)就斷 線(xian),但(dan)(dan)如果放在(zai)好(hao)的(de)(de)伸(shen)(shen)(shen)線(xian)條件,同(tong)樣的(de)(de)桿(gan)(gan)(gan)子,低(di)氧(yang)桿(gan)(gan)(gan)說(shuo)不定(ding)就能(neng)拉到雙零(ling)五,而(er)普通無(wu)氧(yang)桿(gan)(gan)(gan)最多只能(neng)拉伸(shen)(shen)(shen)到0.1而(er)已,當然做(zuo)(zuo)的(de)(de)最細(xi)的(de)(de)如雙零(ling)二卻非得依靠(kao)進口的(de)(de) 無(wu)氧(yang)銅桿(gan)(gan)(gan)了.目(mu)前有(you)企業嘗(chang)試用剝皮的(de)(de)方式來處理低(di)氧(yang)桿(gan)(gan)(gan)來伸(shen)(shen)(shen)0.03線(xian).但(dan)(dan)有(you)關這方面的(de)(de)內容(rong)我(wo)還(huan)不是(shi)很清(qing)楚。
音響線(xian)一般反而喜歡用無氧(yang)桿(gan)(gan),這和無氧(yang)桿(gan)(gan)是單晶銅,低(di)氧(yang)桿(gan)(gan)是多晶銅有關。
氧銅桿和無氧銅桿由于制造方法的不同,致使存在差(cha)別,具有各自(zi)的特點。
一、關于氧(yang)的(de)吸入和脫去以及它的(de)存在狀態
生產(chan)(chan)銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)陰(yin)極銅(tong)(tong)(tong)的(de)(de)(de)含(han)(han)氧(yang)(yang)(yang)(yang)(yang)量(liang)一(yi)般(ban)在(zai)(zai)10—50ppm,在(zai)(zai)常(chang)溫(wen)下(xia)氧(yang)(yang)(yang)(yang)(yang)在(zai)(zai)銅(tong)(tong)(tong)中的(de)(de)(de)固(gu)溶度約2ppm。低氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)含(han)(han)氧(yang)(yang)(yang)(yang)(yang)量(liang)一(yi)般(ban)在(zai)(zai)200(175)—400(450)ppm,因此氧(yang)(yang)(yang)(yang)(yang)的(de)(de)(de)進入是(shi)(shi)在(zai)(zai)銅(tong)(tong)(tong)的(de)(de)(de)液態下(xia)吸入的(de)(de)(de),而上引法(fa)無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則相(xiang)(xiang)反,氧(yang)(yang)(yang)(yang)(yang)在(zai)(zai)液態銅(tong)(tong)(tong)下(xia)保持相(xiang)(xiang)當時間(jian)后,被還原而脫去,通常(chang)這(zhe)種桿(gan)(gan)的(de)(de)(de)含(han)(han)氧(yang)(yang)(yang)(yang)(yang)量(liang)都在(zai)(zai)10—50ppm以(yi)(yi)(yi)下(xia),最(zui)低可達1-2ppm,從組(zu)織上看,低氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)(de)氧(yang)(yang)(yang)(yang)(yang),以(yi)(yi)(yi)氧(yang)(yang)(yang)(yang)(yang)化銅(tong)(tong)(tong)狀態,存在(zai)(zai)于晶(jing)粒邊界附近,這(zhe)對低氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)而言可以(yi)(yi)(yi)說是(shi)(shi)常(chang)見(jian)的(de)(de)(de)但對無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則很(hen)少見(jian)。氧(yang)(yang)(yang)(yang)(yang)化銅(tong)(tong)(tong)以(yi)(yi)(yi)夾(jia)雜形式在(zai)(zai)晶(jing)界出現對材料的(de)(de)(de)韌性(xing)產(chan)(chan)生負面(mian)影響(xiang)。而無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)(de)氧(yang)(yang)(yang)(yang)(yang)很(hen)低,所以(yi)(yi)(yi)這(zhe)種銅(tong)(tong)(tong)的(de)(de)(de)組(zu)織是(shi)(shi)均(jun)勻的(de)(de)(de)單相(xiang)(xiang)組(zu)織對韌性(xing)有利。在(zai)(zai)無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)中的(de)(de)(de)多孔(kong)性(xing)是(shi)(shi)不常(chang)見(jian)的(de)(de)(de),而在(zai)(zai)低氧(yang)(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(yi)種缺陷。
二、熱軋組織和鑄(zhu)造組織的區別
低(di)氧(yang)銅(tong)桿由(you)于經過(guo)熱軋,所以(yi)(yi)其(qi)組織(zhi)屬熱加工(gong)組織(zhi),原(yuan)來的(de)(de)(de)(de)鑄造組織(zhi)已經破(po)碎,在(zai)8mm的(de)(de)(de)(de)桿時已有再結晶(jing)(jing)(jing)(jing)的(de)(de)(de)(de)形式出現,而無(wu)氧(yang)銅(tong)桿屬鑄造組織(zhi),晶(jing)(jing)(jing)(jing)粒(li)粗大,這是(shi)為(wei)什么,無(wu)氧(yang)銅(tong)的(de)(de)(de)(de)再結晶(jing)(jing)(jing)(jing)溫度(du)較(jiao)高(gao),需(xu)(xu)要較(jiao)高(gao)退(tui)(tui)火(huo)溫度(du)的(de)(de)(de)(de)固有原(yuan)因(yin)(yin)。這是(shi)因(yin)(yin)為(wei),再結晶(jing)(jing)(jing)(jing)發生在(zai)晶(jing)(jing)(jing)(jing)粒(li)邊(bian)界(jie)附(fu)近,無(wu)氧(yang)銅(tong)桿組織(zhi)晶(jing)(jing)(jing)(jing)粒(li)粗大,晶(jing)(jing)(jing)(jing)粒(li)尺寸甚至能達幾個毫米,因(yin)(yin)而晶(jing)(jing)(jing)(jing)粒(li)邊(bian)界(jie)少(shao),即使通過(guo)拉制變形,但晶(jing)(jing)(jing)(jing)粒(li)邊(bian)界(jie)相對(dui)低(di)氧(yang)銅(tong)桿還是(shi)較(jiao)少(shao),所以(yi)(yi)需(xu)(xu)要較(jiao)高(gao)的(de)(de)(de)(de)退(tui)(tui)火(huo)功率(lv)。對(dui)無(wu)氧(yang)銅(tong)成功的(de)(de)(de)(de)退(tui)(tui)火(huo)要求是(shi):由(you)桿經拉制,但尚未鑄造組織(zhi)的(de)(de)(de)(de)線時的(de)(de)(de)(de)第一次退(tui)(tui)火(huo),其(qi)退(tui)(tui)火(huo)功率(lv)應(ying)比同(tong)樣(yang)情(qing)況(kuang)的(de)(de)(de)(de)低(di)氧(yang)銅(tong)高(gao)10——15%。經繼(ji)續拉制,在(zai)以(yi)(yi)后階段的(de)(de)(de)(de)退(tui)(tui)火(huo)功率(lv)應(ying)留有足(zu)夠的(de)(de)(de)(de)余量和對(dui)低(di)氧(yang)銅(tong)和無(wu)氧(yang)銅(tong)切實(shi)區(qu)別執行不同(tong)的(de)(de)(de)(de)退(tui)(tui)火(huo)工(gong)藝,以(yi)(yi)保證(zheng)在(zai)制品和成品導線的(de)(de)(de)(de)柔軟性。
三(san)、夾雜,氧含量波動,表面氧化物和可能存在的熱軋缺陷的差別
無(wu)(wu)氧(yang)(yang)(yang)銅(tong)桿的(de)(de)(de)可(ke)拉性在(zai)所有線徑里(li)與低氧(yang)(yang)(yang)銅(tong)桿相比都(dou)是(shi)優(you)越(yue)的(de)(de)(de),除上述組織原因外,無(wu)(wu)氧(yang)(yang)(yang)銅(tong)桿夾(jia)雜少,含氧(yang)(yang)(yang)量穩定,無(wu)(wu)熱(re)軋可(ke)能產(chan)生的(de)(de)(de)缺陷,桿表氧(yang)(yang)(yang)化(hua)(hua)物(wu)厚度可(ke)達≤15A。在(zai)連鑄連軋生產(chan)過程中如(ru)果(guo)工(gong)藝不穩定,對氧(yang)(yang)(yang)監控不嚴,含氧(yang)(yang)(yang)量不穩定將直(zhi)接影響桿的(de)(de)(de)性能。如(ru)果(guo)桿的(de)(de)(de)表面氧(yang)(yang)(yang)化(hua)(hua)物(wu)能在(zai)后工(gong)序(xu)的(de)(de)(de)連續(xu)清洗中得(de)以彌補外,但比較(jiao)麻煩的(de)(de)(de)是(shi)有相當多的(de)(de)(de)氧(yang)(yang)(yang)化(hua)(hua)物(wu)存在(zai)于“皮(pi)下”,對拉線斷線影響更(geng)直(zhi)接,故而在(zai)拉制(zhi)微細(xi)線,超(chao)微細(xi)線時,為了減少斷線,有時要對銅(tong)桿采(cai)取不得(de)已的(de)(de)(de)辦法——剝(bo)(bo)皮(pi),甚(shen)至二次(ci)剝(bo)(bo)皮(pi)的(de)(de)(de)原因所在(zai),目的(de)(de)(de)要除去皮(pi)下氧(yang)(yang)(yang)化(hua)(hua)物(wu)。
四(si)、低氧銅(tong)桿和無氧銅(tong)桿的韌性有差別
兩(liang)者都可以(yi)拉(la)到0.015mm,但在低溫超導線(xian)中的(de)低溫級(ji)無氧(yang)銅,其細絲間(jian)的(de)間(jian)距(ju)只有0.001mm.
五、從(cong)制桿(gan)的原(yuan)材料到制線的經濟性有(you)差別。
制造無氧(yang)(yang)銅(tong)桿要(yao)求質量較高(gao)的原(yuan)材料。一般,拉制直徑>1mm的銅(tong)線(xian)時(shi),低氧(yang)(yang)銅(tong)桿的優(you)點比較明顯(xian),而(er)無氧(yang)(yang)銅(tong)桿顯(xian)得更(geng)為優(you)越的是拉制直徑<0.5mm的銅(tong)線(xian)。
六、低氧銅桿的制線工(gong)藝與無(wu)氧銅桿的有所(suo)不同。
低(di)氧(yang)銅(tong)(tong)桿的(de)制(zhi)線(xian)工(gong)藝(yi)(yi)不(bu)能(neng)照(zhao)搬(ban)到無氧(yang)銅(tong)(tong)桿的(de)制(zhi)線(xian)工(gong)藝(yi)(yi)上來,至(zhi)少兩(liang)者的(de)退(tui)火(huo)工(gong)藝(yi)(yi)是不(bu)同的(de)。因為線(xian)的(de)柔軟(ruan)性深受(shou)材(cai)料(liao)成份和制(zhi)桿,制(zhi)線(xian)和退(tui)火(huo)工(gong)藝(yi)(yi)的(de)影響,不(bu)能(neng)簡單地(di)說(shuo)低(di)氧(yang)銅(tong)(tong)或(huo)無氧(yang)銅(tong)(tong)誰軟(ruan)誰硬。