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來源:行業動態 閱(yue)讀:109594 發布時間(jian):2019-07-05
導讀:由于生(sheng)產(chan)銅(tong)桿(gan)的(de)兩(liang)者(zhe)的(de)工(gong)(gong)藝(yi)不(bu)同,所生(sheng)產(chan)的(de)銅(tong)桿(gan)中的(de)含(han)(han)氧(yang)(yang)(yang)量(liang)及外(wai)觀就不(bu)同。上引生(sheng)產(chan)的(de)銅(tong)桿(gan),工(gong)(gong)藝(yi)得當(dang)氧(yang)(yang)(yang)含(han)(han)量(liang)在(zai)(zai)10ppm以下(xia)(xia),叫(jiao)(jiao)無氧(yang)(yang)(yang)銅(tong)桿(gan);連鑄連鑄生(sheng)產(chan)的(de)銅(tong)桿(gan) 是在(zai)(zai)保護條件下(xia)(xia)的(de)熱軋,氧(yang)(yang)(yang)含(han)(han)量(liang)在(zai)(zai)200-500ppm范(fan)圍內,但有時(shi)也高(gao)達700ppm以上,一般情況(kuang)下(xia)(xia),此(ci)種方法生(sheng)產(chan)的(de)銅(tong)外(wai)表光(guang)亮,低氧(yang)(yang)(yang)銅(tong)桿(gan),有時(shi)也叫(jiao)(jiao)光(guang)桿(gan)。
銅桿是(shi)(shi)電纜行業的(de)(de)(de)主要原料,生(sheng)產的(de)(de)(de)方(fang)式主要有兩(liang)種——連(lian)鑄(zhu)連(lian)軋(ya)法和(he)上(shang)引(yin)(yin)連(lian)鑄(zhu)法。連(lian)鑄(zhu)連(lian)軋(ya)低(di)氧(yang)銅桿的(de)(de)(de)生(sheng)產方(fang)法較多,其特點是(shi)(shi)金屬在(zai)豎爐中(zhong)融(rong)化后(hou),銅液通過保溫爐、溜槽、中(zhong)間包,從(cong)澆管進(jin)(jin)入封閉的(de)(de)(de)模腔內,采(cai)用較大(da)的(de)(de)(de)冷卻強度進(jin)(jin)行冷卻,形成鑄(zhu)坯(pi),然后(hou)進(jin)(jin)行多道次軋(ya)制,生(sheng)產的(de)(de)(de)低(di)氧(yang)銅桿為熱加工(gong)(gong)組(zu)(zu)織(zhi)(zhi),原來的(de)(de)(de)鑄(zhu)造(zao)組(zu)(zu)織(zhi)(zhi)已經破碎,含氧(yang)量一(yi)般為200~400ppm之間。無(wu)氧(yang)銅桿國內基本(ben)全(quan)部采(cai)用上(shang)引(yin)(yin)連(lian)鑄(zhu)法生(sheng)產,金屬在(zai)感應電爐中(zhong)融(rong)化后(hou)通過石墨模進(jin)(jin)行上(shang)引(yin)(yin)連(lian)續鑄(zhu)造(zao),之后(hou)進(jin)(jin)行冷軋(ya)或冷加工(gong)(gong),生(sheng)產的(de)(de)(de)無(wu)氧(yang)銅桿為鑄(zhu)造(zao)組(zu)(zu)織(zhi)(zhi),含氧(yang)量一(yi)般在(zai)20ppm以下。由于制造(zao)工(gong)(gong)藝的(de)(de)(de)不同,所(suo)以在(zai)組(zu)(zu)織(zhi)(zhi)結(jie)構、氧(yang)含量分(fen)布、雜質的(de)(de)(de)形式及(ji)分(fen)布等諸多方(fang)面有較大(da)差(cha)別。
一、拉制性能
銅桿(gan)的(de)(de)拉(la)制性能(neng)跟很多因素有關,如雜質的(de)(de)含量(liang)、氧含量(liang)及分布(bu)、工藝控制等。下面(mian)分別從以上幾個方面(mian)對(dui)銅桿(gan)的(de)(de)拉(la)制性能(neng)進行分析。
1、熔化方(fang)式對S等雜(za)質的影響
連(lian)鑄(zhu)(zhu)連(lian)軋(ya)生產銅(tong)(tong)桿主要是(shi)(shi)通(tong)(tong)過(guo)氣體的燃燒使銅(tong)(tong)桿熔(rong)化,在(zai)燃燒的過(guo)程中,通(tong)(tong)過(guo)氧化和揮發(fa)作用(yong),可一(yi)定(ding)程度減少部分雜質進入(ru)(ru)銅(tong)(tong)液,因此連(lian)鑄(zhu)(zhu)連(lian)軋(ya)法對(dui)原料要求相對(dui)低一(yi)些(xie)。上引連(lian)鑄(zhu)(zhu)生產無氧銅(tong)(tong)桿,由于是(shi)(shi)用(yong)感應電爐熔(rong)化,電解銅(tong)(tong)表(biao)面的“銅(tong)(tong)綠”“銅(tong)(tong)豆”基本都(dou)熔(rong)入(ru)(ru)到(dao)銅(tong)(tong)液中。其中熔(rong)入(ru)(ru)的S對(dui)無氧銅(tong)(tong)桿塑性影響(xiang)極大,會增(zeng)加拉絲斷線率。
2、鑄造過程(cheng)中雜質的進入
在(zai)(zai)生產(chan)過(guo)程中(zhong)(zhong),連(lian)鑄連(lian)軋(ya)工藝需通(tong)(tong)過(guo)保溫爐(lu)(lu)、溜槽、中(zhong)(zhong)間包轉運(yun)銅液(ye),相對容易(yi)造(zao)成耐火材(cai)(cai)料(liao)的(de)(de)剝落,在(zai)(zai)軋(ya)制過(guo)程中(zhong)(zhong)需要通(tong)(tong)過(guo)軋(ya)輥,造(zao)成鐵質的(de)(de)脫落,會(hui)給銅桿(gan)(gan)造(zao)成外部(bu)夾雜(za)。而熱軋(ya)中(zhong)(zhong)皮(pi)上和皮(pi)下氧化(hua)物的(de)(de)軋(ya)入,會(hui)給低氧桿(gan)(gan)的(de)(de)拉絲造(zao)成不利(li)的(de)(de)影(ying)響。上引連(lian)鑄法生產(chan)工藝流程較(jiao)短,銅液(ye)是通(tong)(tong)過(guo)聯體爐(lu)(lu)內潛流式完成,對耐火材(cai)(cai)料(liao)的(de)(de)沖(chong)擊不大(da),結(jie)晶(jing)是通(tong)(tong)過(guo)石(shi)墨模內進(jin)(jin)行,所以過(guo)程中(zhong)(zhong)可能(neng)產(chan)生的(de)(de)污染源較(jiao)少(shao),雜(za)質進(jin)(jin)入的(de)(de)機會(hui)較(jiao)少(shao)。
O、S、P是(shi)與銅(tong)(tong)(tong)(tong)會(hui)生(sheng)產化合物的(de)元素。在熔態(tai)銅(tong)(tong)(tong)(tong)中,氧可以溶(rong)解一部分(fen),但當銅(tong)(tong)(tong)(tong)冷(leng)凝時(shi)(shi),氧幾乎不溶(rong)解于銅(tong)(tong)(tong)(tong)中。熔態(tai)時(shi)(shi)所溶(rong)解的(de)氧,以銅(tong)(tong)(tong)(tong)=氧化亞銅(tong)(tong)(tong)(tong)共(gong)晶(jing)(jing)(jing)體析出(chu),分(fen)布在晶(jing)(jing)(jing)粒晶(jing)(jing)(jing)界處。銅(tong)(tong)(tong)(tong)-氧化亞銅(tong)(tong)(tong)(tong)共(gong)晶(jing)(jing)(jing)體的(de)出(chu)現,顯著降低了(le)銅(tong)(tong)(tong)(tong)的(de)塑性。
硫可以溶(rong)解在熔體的銅(tong)中,但在室溫下,其(qi)溶(rong)解度(du)幾乎降(jiang)低到零,它(ta)以硫化亞銅(tong)的形(xing)式出現在晶粒晶界處,會顯著(zhu)降(jiang)低銅(tong)的塑性。
3、氧(yang)(yang)在低氧(yang)(yang)銅桿和無氧(yang)(yang)銅桿中分(fen)布形式及其(qi)影響
氧(yang)(yang)含(han)量對低(di)氧(yang)(yang)銅桿的(de)(de)拉線(xian)性能(neng)有著(zhu)明(ming)顯(xian)的(de)(de)影響。當氧(yang)(yang)含(han)量增加到最佳值時,銅桿的(de)(de)斷線(xian)率最低(di)。這是因為(wei)氧(yang)(yang)在與大部(bu)分雜質(zhi)反應的(de)(de)過程中(zhong)(zhong)都起到了清(qing)除器的(de)(de)作(zuo)用。適(shi)度的(de)(de)氧(yang)(yang)還有利于去除銅液中(zhong)(zhong)的(de)(de)氫,生成(cheng)水蒸氣溢出(chu),減少(shao)氣孔的(de)(de)形成(cheng)。最佳的(de)(de)氧(yang)(yang)含(han)量為(wei)拉線(xian)工藝提供了最好的(de)(de)條(tiao)件。
低氧(yang)銅(tong)桿(gan)氧(yang)化物(wu)(wu)的(de)(de)(de)分(fen)布(bu)(bu):在連續(xu)(xu)澆鑄(zhu)中(zhong)凝固(gu)的(de)(de)(de)最(zui)初(chu)階段,散(san)熱(re)(re)速率和(he)均(jun)勻冷卻是決定銅(tong)桿(gan)氧(yang)化物(wu)(wu)分(fen)布(bu)(bu)的(de)(de)(de)主(zhu)要因素。不均(jun)勻冷卻會引起(qi)銅(tong)桿(gan)內部結(jie)構本質上的(de)(de)(de)差異,但后續(xu)(xu)的(de)(de)(de)熱(re)(re)加工,柱(zhu)狀晶通常會遭到破壞,使氧(yang)化亞銅(tong)顆粒(li)(li)細(xi)微(wei)化和(he)均(jun)勻分(fen)布(bu)(bu)。氧(yang)化物(wu)(wu)顆粒(li)(li)聚集而產生的(de)(de)(de)典型情況是中(zhong)心(xin)爆裂。除氧(yang)化物(wu)(wu)顆粒(li)(li)分(fen)布(bu)(bu)的(de)(de)(de)影響外,具有較(jiao)小(xiao)氧(yang)化物(wu)(wu)顆粒(li)(li)的(de)(de)(de)銅(tong)桿(gan)顯示出較(jiao)好的(de)(de)(de)拉線特(te)性,較(jiao)大(da)的(de)(de)(de)Cu2O顆粒(li)(li)容易造(zao)成應力(li)集中(zhong)點而斷裂。
無(wu)氧(yang)(yang)銅(tong)含(han)(han)氧(yang)(yang)量(liang)(liang)超(chao)標,銅(tong)桿(gan)變脆(cui),延(yan)伸(shen)(shen)率下降(jiang)(jiang),拉伸(shen)(shen)式(shi)樣端口顯暗紅色,結(jie)晶組(zu)織疏松。當氧(yang)(yang)含(han)(han)量(liang)(liang)超(chao)出8ppm時,工藝(yi)性(xing)能(neng)變差,表現為鑄造及拉伸(shen)(shen)過程中(zhong)斷(duan)(duan)桿(gan)及斷(duan)(duan)線率極具增高(gao)(gao)。這是由(you)于(yu)氧(yang)(yang)能(neng)與銅(tong)生成氧(yang)(yang)化亞(ya)(ya)銅(tong)脆(cui)性(xing)相(xiang),形成銅(tong)-氧(yang)(yang)化亞(ya)(ya)銅(tong)共晶體,以(yi)網狀組(zu)織分布在境界上。這種(zhong)脆(cui)性(xing)相(xiang)硬度高(gao)(gao),在冷變形時將會與銅(tong)機體脫離,導(dao)致銅(tong)桿(gan)的(de)機械(xie)性(xing)能(neng)下降(jiang)(jiang),在后續(xu)加工中(zhong)容易(yi)造成斷(duan)(duan)裂現象(xiang)。氧(yang)(yang)含(han)(han)量(liang)(liang)高(gao)(gao)還(huan)能(neng)導(dao)致無(wu)氧(yang)(yang)銅(tong)桿(gan)導(dao)電率下降(jiang)(jiang)。因此,必須嚴(yan)格控制上引(yin)連鑄工藝(yi)及產品質量(liang)(liang)。
4、氫的影響
在(zai)上引(yin)連鑄(zhu)中,氧含量控(kong)制較低,氧化物的副(fu)作用唄**降低,但氫(qing)的影響成為較顯著的問題(ti)。吸氣后熔體中存在(zai)平衡反應:H2O(g)=[O]+2[H];
氣(qi)(qi)體及疏(shu)松是(shi)在結晶(jing)(jing)(jing)的(de)(de)(de)過程中(zhong),氫(qing)從過飽和(he)的(de)(de)(de)溶液(ye)(ye)中(zhong)析(xi)(xi)出(chu)(chu)并聚集(ji)而(er)形(xing)成(cheng)(cheng)(cheng)的(de)(de)(de)。在結晶(jing)(jing)(jing)前(qian)(qian)析(xi)(xi)出(chu)(chu)的(de)(de)(de)氫(qing)又可還原氧化亞銅(tong)而(er)生成(cheng)(cheng)(cheng)水(shui)氣(qi)(qi)泡。由于上(shang)引(yin)(yin)鑄(zhu)造的(de)(de)(de)特(te)點是(shi)銅(tong)液(ye)(ye)自上(shang)而(er)下的(de)(de)(de)結晶(jing)(jing)(jing),形(xing)成(cheng)(cheng)(cheng)的(de)(de)(de)液(ye)(ye)**形(xing)狀近似錐型。銅(tong)液(ye)(ye)結晶(jing)(jing)(jing)前(qian)(qian)析(xi)(xi)出(chu)(chu)的(de)(de)(de)氣(qi)(qi)體在上(shang)浮過程中(zhong)被(bei)堵在凝固組織(zhi)內,結晶(jing)(jing)(jing)時(shi)(shi)在鑄(zhu)桿(gan)內形(xing)成(cheng)(cheng)(cheng)氣(qi)(qi)孔(kong)。上(shang)引(yin)(yin)的(de)(de)(de)含氣(qi)(qi)量(liang)(liang)少時(shi)(shi),析(xi)(xi)出(chu)(chu)的(de)(de)(de)氫(qing)存在于晶(jing)(jing)(jing)界處,形(xing)成(cheng)(cheng)(cheng)疏(shu)松;含氣(qi)(qi)量(liang)(liang)多(duo)時(shi)(shi),則聚集(ji)成(cheng)(cheng)(cheng)氣(qi)(qi)孔(kong),因此,氣(qi)(qi)孔(kong)和(he)疏(shu)松是(shi)氫(qing)氣(qi)(qi)和(he)水(shui)蒸氣(qi)(qi)兩者(zhe)形(xing)成(cheng)(cheng)(cheng)的(de)(de)(de)。
氫來源于上引(yin)生產過程中(zhong)(zhong)的各(ge)個工(gong)藝環節,如原(yuan)料電(dian)解銅(tong)的“銅(tong)綠”、輔料木炭(tan)**、氣(qi)候(hou)環境(jing)**、石墨結晶(jing)器未干(gan)燥等。因此,熔化(hua)爐(lu)中(zhong)(zhong)的銅(tong)液表面應(ying)覆蓋(gai)經烘(hong)烤的木炭(tan),電(dian)解銅(tong)應(ying)盡量去除“銅(tong)綠”、“銅(tong)豆”“耳朵”,對提高無氧銅(tong)桿質量非常重(zhong)要。
在連鑄連軋工藝(yi)中,往往采用適(shi)度控(kong)制氧含量來(lai)控(kong)制氫。Cu2O+ H2= 2Cu+ H2O
由于銅液在(zai)鑄造過程中(zhong)是(shi)自(zi)下(xia)而(er)上(shang)結晶(jing),銅液中(zhong)的(de)氧和氫所產生的(de)水蒸氣很容易上(shang)浮(fu)跑出,銅液中(zhong)的(de)氫大(da)部分能被有效去除,因(yin)而(er)對銅桿(gan)的(de)影響較小。
二、表面質量
在(zai)生產電磁線等產品(pin)的(de)過程(cheng)中(zhong),對銅(tong)桿的(de)表面質量也需提出(chu)要求(qiu)。需要拉制后(hou)的(de)銅(tong)絲(si)表面無毛刺(ci)、銅(tong)粉(fen)少、無油污(wu)。并通過扭轉(zhuan)試驗測量表面銅(tong)粉(fen)的(de)質量和扭轉(zhuan)后(hou)觀察銅(tong)桿的(de)復原(yuan)情況來判定其好壞。
在(zai)連鑄連軋(ya)(ya)過(guo)程中,從鑄造到軋(ya)(ya)制前,溫度高(gao),完全暴露(lu)于(yu)空氣(qi)中,使鑄坯表面(mian)形成較厚的氧化層,在(zai)軋(ya)(ya)制過(guo)程中,隨著軋(ya)(ya)輥的轉動,氧化物顆(ke)粒軋(ya)(ya)入銅(tong)線表面(mian)。由于(yu)氧化亞銅(tong)是高(gao)熔點脆性化合物,對于(yu)軋(ya)(ya)入較深的氧化亞銅(tong),當成條狀(zhuang)的聚(ju)集物遇(yu)模具(ju)拉伸時(shi),就會是銅(tong)桿外表面(mian)產生毛刺(ci),給(gei)后續的涂漆造成麻煩。
而上引連鑄(zhu)工藝制(zhi)(zhi)造的無氧(yang)(yang)銅(tong)(tong)桿(gan),由于鑄(zhu)造和(he)冷卻完全與氧(yang)(yang)隔絕(jue),后(hou)續亦無熱軋過(guo)程,銅(tong)(tong)桿(gan)表面無軋入表面的氧(yang)(yang)化物(wu),質量(liang)較好(hao),拉制(zhi)(zhi)后(hou)銅(tong)(tong)粉少(shao),上述問題較少(shao)存在(zai)。
無(wu)氧銅(tong)桿(gan)也(ye)分(fen)進口設(she)(she)備(bei)做的(de)(de)(de)和國產(chan)(chan)(chan)設(she)(she)備(bei)做的(de)(de)(de),但目(mu)前(qian)進口產(chan)(chan)(chan)品(pin)已無(wu)明顯優勢,銅(tong)桿(gan)產(chan)(chan)(chan)品(pin)出來后區(qu)別不是很大,只要(yao)銅(tong)板(ban)選的(de)(de)(de)好(hao),生(sheng)產(chan)(chan)(chan)控制比較穩定,國產(chan)(chan)(chan)設(she)(she)備(bei)也(ye)能產(chan)(chan)(chan)出可(ke)拉伸(shen)0.05的(de)(de)(de)銅(tong)桿(gan).進口設(she)(she)備(bei)一般(ban)是芬(fen)蘭奧(ao)托昆普的(de)(de)(de)設(she)(she)備(bei),國產(chan)(chan)(chan)設(she)(she)備(bei)最(zui)好(hao)的(de)(de)(de)應該(gai)是上海的(de)(de)(de)海軍(jun)廠的(de)(de)(de)了,生(sheng)產(chan)(chan)(chan)時間最(zui)長(chang),軍(jun)工企業,質量可(ke)靠。
低氧銅桿(gan)進口設(she)備國(guo)際主(zhu)要有(you)兩種(zhong)(zhong),一種(zhong)(zhong)是(shi)美國(guo)南(nan)線(xian)設(she)備,英文是(shi)SOUTHWIRE,國(guo)內(nei)廠(chang)(chang)家是(shi)南(nan)京華新,江西(xi)銅業,另一種(zhong)(zhong)是(shi)德國(guo)CONTIROD設(she)備,國(guo)內(nei)廠(chang)(chang)家是(shi)常(chang)州金源(yuan),天津(jin)大(da)無(wu)縫。
無(wu)(wu)氧(yang)(yang)及低(di)氧(yang)(yang)桿(gan)(gan)(gan)從含氧(yang)(yang)量(liang)上(shang)容易區別(bie),無(wu)(wu)氧(yang)(yang)銅是(shi)含氧(yang)(yang)量(liang)在(zai)(zai)(zai)10-20個(ge)(ge)PPM以下,但目前(qian)有(you)(you)的(de)廠家只(zhi)能做(zuo)到(dao)50個(ge)(ge)PPM以下.低(di)氧(yang)(yang)銅桿(gan)(gan)(gan)在(zai)(zai)(zai) 200-400個(ge)(ge)PPM,好(hao)(hao)的(de)桿(gan)(gan)(gan)子(zi)一(yi)般(ban)含氧(yang)(yang)量(liang)控制在(zai)(zai)(zai)250個(ge)(ge)PPM左右,無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)一(yi)般(ban)采(cai)取的(de)是(shi)上(shang)引法,低(di)氧(yang)(yang)桿(gan)(gan)(gan)是(shi)連鑄(zhu)連軋(ya),兩種產品相對而(er)言低(di)氧(yang)(yang)桿(gan)(gan)(gan)對漆包線(xian)(xian)(xian)(xian)性 能更適(shi)應些(xie),如(ru)柔軟性,回彈角(jiao),繞線(xian)(xian)(xian)(xian)性能.但低(di)氧(yang)(yang)桿(gan)(gan)(gan)對拉(la)(la)絲(si)條件(jian)相對要苛刻些(xie),同樣(yang)拉(la)(la)伸(shen)(shen)0.2的(de)細(xi)(xi)絲(si),如(ru)果伸(shen)(shen)線(xian)(xian)(xian)(xian)條件(jian)不(bu)好(hao)(hao),普(pu)通的(de)無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)可拉(la)(la)而(er)好(hao)(hao)的(de)低(di)氧(yang)(yang)桿(gan)(gan)(gan)就(jiu)斷 線(xian)(xian)(xian)(xian),但如(ru)果放在(zai)(zai)(zai)好(hao)(hao)的(de)伸(shen)(shen)線(xian)(xian)(xian)(xian)條件(jian),同樣(yang)的(de)桿(gan)(gan)(gan)子(zi),低(di)氧(yang)(yang)桿(gan)(gan)(gan)說不(bu)定就(jiu)能拉(la)(la)到(dao)雙零(ling)五,而(er)普(pu)通無(wu)(wu)氧(yang)(yang)桿(gan)(gan)(gan)最多只(zhi)能拉(la)(la)伸(shen)(shen)到(dao)0.1而(er)已(yi),當然做(zuo)的(de)最細(xi)(xi)的(de)如(ru)雙零(ling)二(er)卻非(fei)得依靠進口的(de) 無(wu)(wu)氧(yang)(yang)銅桿(gan)(gan)(gan)了(le).目前(qian)有(you)(you)企業嘗試用剝皮的(de)方式來(lai)處理低(di)氧(yang)(yang)桿(gan)(gan)(gan)來(lai)伸(shen)(shen)0.03線(xian)(xian)(xian)(xian).但有(you)(you)關這(zhe)方面的(de)內容我還不(bu)是(shi)很清楚。
音響線一般反而喜歡用無氧(yang)桿(gan),這(zhe)和無氧(yang)桿(gan)是(shi)單晶(jing)銅,低氧(yang)桿(gan)是(shi)多晶(jing)銅有關。
氧銅桿和無氧銅桿由于制(zhi)造方(fang)法(fa)的不(bu)同,致使(shi)存在差(cha)別,具有各自的特(te)點(dian)。
一、關(guan)于氧(yang)的吸入和(he)脫去以及它的存在狀態
生(sheng)產銅(tong)(tong)(tong)桿(gan)的(de)(de)陰極銅(tong)(tong)(tong)的(de)(de)含氧(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)在(zai)(zai)銅(tong)(tong)(tong)中的(de)(de)固(gu)溶(rong)度約(yue)2ppm。低氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)的(de)(de)含氧(yang)(yang)(yang)量(liang)一(yi)般(ban)在(zai)(zai)200(175)—400(450)ppm,因(yin)此氧(yang)(yang)(yang)的(de)(de)進入是在(zai)(zai)銅(tong)(tong)(tong)的(de)(de)液(ye)態(tai)下(xia)吸入的(de)(de),而上引法(fa)無(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)則相(xiang)反(fan),氧(yang)(yang)(yang)在(zai)(zai)液(ye)態(tai)銅(tong)(tong)(tong)下(xia)保持相(xiang)當時(shi)間后,被還(huan)原(yuan)而脫去,通(tong)常(chang)這種桿(gan)的(de)(de)含氧(yang)(yang)(yang)量(liang)都在(zai)(zai)10—50ppm以下(xia),最低可達1-2ppm,從組織(zhi)上看,低氧(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)氧(yang)(yang)(yang),以氧(yang)(yang)(yang)化銅(tong)(tong)(tong)狀態(tai),存在(zai)(zai)于晶(jing)粒邊界(jie)附近,這對(dui)低氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)而言可以說是常(chang)見的(de)(de)但對(dui)無(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)則很少見。氧(yang)(yang)(yang)化銅(tong)(tong)(tong)以夾雜(za)形(xing)式在(zai)(zai)晶(jing)界(jie)出現對(dui)材料的(de)(de)韌(ren)性(xing)產生(sheng)負面影響。而無(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)中的(de)(de)氧(yang)(yang)(yang)很低,所以這種銅(tong)(tong)(tong)的(de)(de)組織(zhi)是均勻的(de)(de)單相(xiang)組織(zhi)對(dui)韌(ren)性(xing)有(you)利。在(zai)(zai)無(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)中的(de)(de)多(duo)孔性(xing)是不常(chang)見的(de)(de),而在(zai)(zai)低氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)中則是常(chang)見的(de)(de)一(yi)種缺陷。
二、熱軋組(zu)織(zhi)和(he)鑄造組(zu)織(zhi)的區別
低氧(yang)(yang)銅(tong)(tong)(tong)桿(gan)由于經(jing)過熱軋,所以(yi)其(qi)組織屬熱加工組織,原來的(de)鑄造(zao)組織已(yi)(yi)經(jing)破碎(sui),在8mm的(de)桿(gan)時(shi)已(yi)(yi)有再(zai)結(jie)(jie)晶的(de)形式出(chu)現,而無(wu)氧(yang)(yang)銅(tong)(tong)(tong)桿(gan)屬鑄造(zao)組織,晶粒(li)(li)粗大,這是為什么,無(wu)氧(yang)(yang)銅(tong)(tong)(tong)的(de)再(zai)結(jie)(jie)晶溫度較(jiao)高(gao)(gao),需要(yao)較(jiao)高(gao)(gao)退火溫度的(de)固有原因。這是因為,再(zai)結(jie)(jie)晶發生在晶粒(li)(li)邊界(jie)附近,無(wu)氧(yang)(yang)銅(tong)(tong)(tong)桿(gan)組織晶粒(li)(li)粗大,晶粒(li)(li)尺寸甚(shen)至能達幾個毫米,因而晶粒(li)(li)邊界(jie)少(shao),即使通(tong)過拉制變(bian)形,但晶粒(li)(li)邊界(jie)相對(dui)低氧(yang)(yang)銅(tong)(tong)(tong)桿(gan)還是較(jiao)少(shao),所以(yi)需要(yao)較(jiao)高(gao)(gao)的(de)退火功(gong)率(lv)。對(dui)無(wu)氧(yang)(yang)銅(tong)(tong)(tong)成功(gong)的(de)退火要(yao)求(qiu)是:由桿(gan)經(jing)拉制,但尚未鑄造(zao)組織的(de)線(xian)時(shi)的(de)第一次退火,其(qi)退火功(gong)率(lv)應(ying)比同樣情況的(de)低氧(yang)(yang)銅(tong)(tong)(tong)高(gao)(gao)10——15%。經(jing)繼(ji)續拉制,在以(yi)后階段的(de)退火功(gong)率(lv)應(ying)留有足夠(gou)的(de)余量和(he)對(dui)低氧(yang)(yang)銅(tong)(tong)(tong)和(he)無(wu)氧(yang)(yang)銅(tong)(tong)(tong)切實(shi)區(qu)別執(zhi)行(xing)不同的(de)退火工藝,以(yi)保證在制品和(he)成品導線(xian)的(de)柔軟(ruan)性(xing)。
三、夾雜,氧含量波(bo)動,表面氧化物和可(ke)能存在的熱(re)軋缺陷(xian)的差別(bie)
無(wu)氧(yang)銅桿(gan)(gan)的(de)(de)可拉性(xing)在(zai)所(suo)有(you)(you)線(xian)(xian)(xian)徑(jing)里(li)與(yu)低氧(yang)銅桿(gan)(gan)相比(bi)都是優越的(de)(de),除(chu)上述組織(zhi)原因(yin)外,無(wu)氧(yang)銅桿(gan)(gan)夾雜(za)少,含氧(yang)量穩定(ding),無(wu)熱軋可能產生的(de)(de)缺陷,桿(gan)(gan)表氧(yang)化(hua)物(wu)(wu)(wu)厚度可達≤15A。在(zai)連(lian)(lian)鑄連(lian)(lian)軋生產過程中如(ru)果工(gong)藝不(bu)穩定(ding),對(dui)(dui)氧(yang)監控不(bu)嚴(yan),含氧(yang)量不(bu)穩定(ding)將直(zhi)接(jie)影響桿(gan)(gan)的(de)(de)性(xing)能。如(ru)果桿(gan)(gan)的(de)(de)表面氧(yang)化(hua)物(wu)(wu)(wu)能在(zai)后工(gong)序(xu)的(de)(de)連(lian)(lian)續(xu)清洗(xi)中得(de)以彌補外,但(dan)比(bi)較(jiao)麻煩的(de)(de)是有(you)(you)相當多的(de)(de)氧(yang)化(hua)物(wu)(wu)(wu)存在(zai)于(yu)“皮(pi)下(xia)”,對(dui)(dui)拉線(xian)(xian)(xian)斷線(xian)(xian)(xian)影響更直(zhi)接(jie),故而(er)在(zai)拉制(zhi)微細(xi)線(xian)(xian)(xian),超(chao)微細(xi)線(xian)(xian)(xian)時,為了減少斷線(xian)(xian)(xian),有(you)(you)時要(yao)對(dui)(dui)銅桿(gan)(gan)采取不(bu)得(de)已的(de)(de)辦法——剝皮(pi),甚至二次剝皮(pi)的(de)(de)原因(yin)所(suo)在(zai),目的(de)(de)要(yao)除(chu)去(qu)皮(pi)下(xia)氧(yang)化(hua)物(wu)(wu)(wu)。
四、低氧(yang)銅(tong)桿和(he)無氧(yang)銅(tong)桿的韌性有差(cha)別(bie)
兩者都可以拉到0.015mm,但在低(di)溫超導線(xian)中的低(di)溫級無(wu)氧銅,其細絲間的間距(ju)只有0.001mm.
五(wu)、從制桿(gan)的原材料到制線(xian)的經濟性有差別。
制造無(wu)氧銅桿(gan)要求(qiu)質量較高的(de)原材料。一般,拉制直徑>1mm的(de)銅線時,低氧銅桿(gan)的(de)優點比較明顯,而無(wu)氧銅桿(gan)顯得更為優越的(de)是(shi)拉制直徑<0.5mm的(de)銅線。
六、低氧銅(tong)桿的制(zhi)線工藝(yi)與無氧銅(tong)桿的有所不(bu)同。
低氧銅桿(gan)的(de)制(zhi)線(xian)工藝不能照搬到無氧銅桿(gan)的(de)制(zhi)線(xian)工藝上來,至少兩者(zhe)的(de)退火(huo)工藝是不同的(de)。因為線(xian)的(de)柔(rou)軟(ruan)(ruan)性深(shen)受材料成份和制(zhi)桿(gan),制(zhi)線(xian)和退火(huo)工藝的(de)影響,不能簡(jian)單地說低氧銅或(huo)無氧銅誰軟(ruan)(ruan)誰硬。
下(xia)一條(tiao)額濟納如何分辨劣質線纜(電纜人必備)