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來源(yuan):行業動態 閱讀:109404 發布(bu)時間:2019-07-05
導讀:由于生產銅(tong)(tong)桿(gan)(gan)的(de)(de)兩者的(de)(de)工(gong)藝(yi)不同,所生產的(de)(de)銅(tong)(tong)桿(gan)(gan)中的(de)(de)含(han)氧(yang)(yang)(yang)量(liang)及外觀就(jiu)不同。上引(yin)生產的(de)(de)銅(tong)(tong)桿(gan)(gan),工(gong)藝(yi)得當(dang)氧(yang)(yang)(yang)含(han)量(liang)在10ppm以下,叫無(wu)氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan);連鑄連鑄生產的(de)(de)銅(tong)(tong)桿(gan)(gan) 是在保(bao)護條件下的(de)(de)熱軋,氧(yang)(yang)(yang)含(han)量(liang)在200-500ppm范圍內,但有(you)時也高達700ppm以上,一般情況下,此種方(fang)法生產的(de)(de)銅(tong)(tong)外表光亮,低氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)(gan),有(you)時也叫光桿(gan)(gan)。
銅(tong)(tong)桿是電(dian)纜行(xing)業的(de)主要原料,生(sheng)產(chan)的(de)方(fang)式(shi)主要有兩種——連(lian)(lian)(lian)鑄(zhu)連(lian)(lian)(lian)軋(ya)法(fa)和上(shang)(shang)引連(lian)(lian)(lian)鑄(zhu)法(fa)。連(lian)(lian)(lian)鑄(zhu)連(lian)(lian)(lian)軋(ya)低(di)氧銅(tong)(tong)桿的(de)生(sheng)產(chan)方(fang)法(fa)較(jiao)多(duo),其特點(dian)是金屬在(zai)豎爐(lu)中(zhong)融化(hua)后(hou),銅(tong)(tong)液通(tong)過保(bao)溫爐(lu)、溜槽、中(zhong)間包,從(cong)澆管進(jin)入封閉的(de)模(mo)(mo)腔內,采用較(jiao)大的(de)冷(leng)卻強(qiang)度進(jin)行(xing)冷(leng)卻,形成鑄(zhu)坯,然(ran)后(hou)進(jin)行(xing)多(duo)道次軋(ya)制(zhi),生(sheng)產(chan)的(de)低(di)氧銅(tong)(tong)桿為熱(re)加工組(zu)織,原來的(de)鑄(zhu)造組(zu)織已經破碎,含氧量一般為200~400ppm之間。無(wu)氧銅(tong)(tong)桿國內基本全部采用上(shang)(shang)引連(lian)(lian)(lian)鑄(zhu)法(fa)生(sheng)產(chan),金屬在(zai)感(gan)應電(dian)爐(lu)中(zhong)融化(hua)后(hou)通(tong)過石(shi)墨模(mo)(mo)進(jin)行(xing)上(shang)(shang)引連(lian)(lian)(lian)續鑄(zhu)造,之后(hou)進(jin)行(xing)冷(leng)軋(ya)或冷(leng)加工,生(sheng)產(chan)的(de)無(wu)氧銅(tong)(tong)桿為鑄(zhu)造組(zu)織,含氧量一般在(zai)20ppm以(yi)下。由于(yu)制(zhi)造工藝的(de)不同,所(suo)以(yi)在(zai)組(zu)織結構、氧含量分布、雜質(zhi)的(de)形式(shi)及分布等諸多(duo)方(fang)面有較(jiao)大差別。
一、拉制性能
銅桿的拉(la)制(zhi)性能跟很(hen)多因素有關,如(ru)雜質(zhi)的含(han)量(liang)(liang)、氧含(han)量(liang)(liang)及分(fen)布、工藝控制(zhi)等(deng)。下面(mian)分(fen)別從(cong)以上幾(ji)個方面(mian)對銅桿的拉(la)制(zhi)性能進(jin)行分(fen)析(xi)。
1、熔化方式對S等雜質(zhi)的影響
連鑄(zhu)(zhu)連軋生(sheng)產銅(tong)(tong)(tong)桿主要(yao)是通過氣體的燃燒(shao)使銅(tong)(tong)(tong)桿熔(rong)化(hua),在燃燒(shao)的過程中(zhong)(zhong),通過氧(yang)化(hua)和揮發作用,可一(yi)定程度(du)減(jian)少部分雜質進入銅(tong)(tong)(tong)液,因此連鑄(zhu)(zhu)連軋法(fa)對(dui)原料要(yao)求相對(dui)低一(yi)些。上(shang)引連鑄(zhu)(zhu)生(sheng)產無(wu)氧(yang)銅(tong)(tong)(tong)桿,由于是用感應(ying)電爐熔(rong)化(hua),電解銅(tong)(tong)(tong)表面(mian)的“銅(tong)(tong)(tong)綠”“銅(tong)(tong)(tong)豆”基本(ben)都(dou)熔(rong)入到銅(tong)(tong)(tong)液中(zhong)(zhong)。其(qi)中(zhong)(zhong)熔(rong)入的S對(dui)無(wu)氧(yang)銅(tong)(tong)(tong)桿塑性影響極大,會(hui)增(zeng)加拉絲斷(duan)線率。
2、鑄造過程中雜質的進入(ru)
在(zai)生產過(guo)(guo)程(cheng)(cheng)中(zhong)(zhong),連鑄(zhu)連軋工(gong)藝需(xu)通(tong)過(guo)(guo)保溫(wen)爐、溜槽、中(zhong)(zhong)間包轉運銅液,相對(dui)容易(yi)造(zao)成耐(nai)火材(cai)料的(de)(de)(de)剝落,在(zai)軋制過(guo)(guo)程(cheng)(cheng)中(zhong)(zhong)需(xu)要(yao)通(tong)過(guo)(guo)軋輥,造(zao)成鐵(tie)質的(de)(de)(de)脫落,會給銅桿(gan)造(zao)成外部夾(jia)雜(za)。而熱軋中(zhong)(zhong)皮上(shang)和(he)皮下氧(yang)化物的(de)(de)(de)軋入,會給低氧(yang)桿(gan)的(de)(de)(de)拉絲造(zao)成不(bu)利的(de)(de)(de)影響。上(shang)引(yin)連鑄(zhu)法(fa)生產工(gong)藝流程(cheng)(cheng)較短,銅液是通(tong)過(guo)(guo)聯體爐內潛流式完成,對(dui)耐(nai)火材(cai)料的(de)(de)(de)沖擊(ji)不(bu)大,結晶是通(tong)過(guo)(guo)石(shi)墨模內進行,所以過(guo)(guo)程(cheng)(cheng)中(zhong)(zhong)可(ke)能(neng)產生的(de)(de)(de)污(wu)染源較少,雜(za)質進入的(de)(de)(de)機(ji)會較少。
O、S、P是與銅會(hui)生產化(hua)(hua)合物的元(yuan)素。在(zai)熔態(tai)銅中,氧(yang)(yang)(yang)可以(yi)(yi)溶解一部分,但當銅冷凝時,氧(yang)(yang)(yang)幾乎不(bu)溶解于銅中。熔態(tai)時所溶解的氧(yang)(yang)(yang),以(yi)(yi)銅=氧(yang)(yang)(yang)化(hua)(hua)亞銅共晶體(ti)析出(chu),分布(bu)在(zai)晶粒晶界(jie)處(chu)。銅-氧(yang)(yang)(yang)化(hua)(hua)亞銅共晶體(ti)的出(chu)現,顯著降低了銅的塑(su)性(xing)。
硫(liu)可以溶(rong)解在熔體的銅(tong)中,但(dan)在室溫下,其溶(rong)解度幾乎降低到零,它以硫(liu)化亞銅(tong)的形式出現在晶粒晶界處,會(hui)顯(xian)著降低銅(tong)的塑性。
3、氧在低氧銅桿(gan)和無氧銅桿(gan)中(zhong)分(fen)布形(xing)式及其(qi)影響
氧(yang)含量對低(di)氧(yang)銅桿的(de)(de)拉(la)線(xian)性能有著明顯的(de)(de)影(ying)響。當氧(yang)含量增加到(dao)最(zui)佳值時,銅桿的(de)(de)斷線(xian)率(lv)最(zui)低(di)。這(zhe)是(shi)因為(wei)氧(yang)在與大部分雜質反應的(de)(de)過程中(zhong)都(dou)起到(dao)了清除器的(de)(de)作(zuo)用。適(shi)度(du)的(de)(de)氧(yang)還有利于去除銅液中(zhong)的(de)(de)氫(qing),生成(cheng)水蒸(zheng)氣溢出(chu),減少(shao)氣孔的(de)(de)形成(cheng)。最(zui)佳的(de)(de)氧(yang)含量為(wei)拉(la)線(xian)工(gong)藝提(ti)供了最(zui)好的(de)(de)條件。
低氧銅桿氧化物(wu)的(de)(de)分布(bu):在(zai)連(lian)續澆鑄(zhu)中(zhong)凝固(gu)的(de)(de)最初階段,散熱速(su)率和(he)均(jun)(jun)勻冷(leng)卻(que)是決定銅桿氧化物(wu)分布(bu)的(de)(de)主要因素(su)。不均(jun)(jun)勻冷(leng)卻(que)會引(yin)起銅桿內(nei)部結構本質(zhi)上的(de)(de)差異,但后續的(de)(de)熱加工,柱狀晶通常會遭到破壞,使氧化亞銅顆(ke)(ke)粒(li)細微化和(he)均(jun)(jun)勻分布(bu)。氧化物(wu)顆(ke)(ke)粒(li)聚(ju)集而(er)產生(sheng)的(de)(de)典型情況(kuang)是中(zhong)心爆裂。除氧化物(wu)顆(ke)(ke)粒(li)分布(bu)的(de)(de)影響外(wai),具有較(jiao)小(xiao)氧化物(wu)顆(ke)(ke)粒(li)的(de)(de)銅桿顯示(shi)出較(jiao)好的(de)(de)拉(la)線特性(xing),較(jiao)大的(de)(de)Cu2O顆(ke)(ke)粒(li)容易造成應力集中(zhong)點而(er)斷裂。
無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)含氧(yang)(yang)(yang)(yang)(yang)量(liang)(liang)超標,銅(tong)(tong)(tong)桿(gan)變(bian)脆(cui)(cui),延伸(shen)(shen)率下(xia)降,拉(la)伸(shen)(shen)式樣(yang)端(duan)口顯暗紅色,結晶組(zu)(zu)織疏松。當(dang)氧(yang)(yang)(yang)(yang)(yang)含量(liang)(liang)超出8ppm時,工藝(yi)性(xing)(xing)(xing)能變(bian)差,表現為鑄(zhu)造及拉(la)伸(shen)(shen)過程(cheng)中(zhong)斷桿(gan)及斷線(xian)率極具增(zeng)高。這是(shi)由于氧(yang)(yang)(yang)(yang)(yang)能與銅(tong)(tong)(tong)生(sheng)成(cheng)氧(yang)(yang)(yang)(yang)(yang)化亞銅(tong)(tong)(tong)脆(cui)(cui)性(xing)(xing)(xing)相(xiang),形成(cheng)銅(tong)(tong)(tong)-氧(yang)(yang)(yang)(yang)(yang)化亞銅(tong)(tong)(tong)共晶體,以網狀組(zu)(zu)織分布在境界上。這種脆(cui)(cui)性(xing)(xing)(xing)相(xiang)硬度高,在冷變(bian)形時將會與銅(tong)(tong)(tong)機(ji)體脫離,導(dao)致銅(tong)(tong)(tong)桿(gan)的機(ji)械性(xing)(xing)(xing)能下(xia)降,在后續加(jia)工中(zhong)容易(yi)造成(cheng)斷裂(lie)現象。氧(yang)(yang)(yang)(yang)(yang)含量(liang)(liang)高還能導(dao)致無(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)導(dao)電率下(xia)降。因此(ci),必須(xu)嚴(yan)格控(kong)制(zhi)上引連(lian)鑄(zhu)工藝(yi)及產品質量(liang)(liang)。
4、氫的影響
在(zai)上(shang)引連(lian)鑄(zhu)中,氧含量控制較低,氧化(hua)物的(de)副作用唄(bai)**降低,但氫的(de)影響(xiang)成為較顯著的(de)問題。吸氣后(hou)熔體中存在(zai)平衡反應:H2O(g)=[O]+2[H];
氣(qi)(qi)(qi)體(ti)及疏松是(shi)在(zai)(zai)結晶(jing)的(de)過程中(zhong),氫(qing)從過飽和的(de)溶液(ye)中(zhong)析出(chu)(chu)(chu)(chu)并聚集而(er)形成(cheng)的(de)。在(zai)(zai)結晶(jing)前(qian)析出(chu)(chu)(chu)(chu)的(de)氫(qing)又可還原(yuan)氧化亞(ya)銅而(er)生(sheng)成(cheng)水氣(qi)(qi)(qi)泡。由于(yu)上(shang)引鑄(zhu)造的(de)特點是(shi)銅液(ye)自上(shang)而(er)下的(de)結晶(jing),形成(cheng)的(de)液(ye)**形狀(zhuang)近(jin)似錐型。銅液(ye)結晶(jing)前(qian)析出(chu)(chu)(chu)(chu)的(de)氣(qi)(qi)(qi)體(ti)在(zai)(zai)上(shang)浮過程中(zhong)被堵(du)在(zai)(zai)凝固組織內,結晶(jing)時(shi)在(zai)(zai)鑄(zhu)桿內形成(cheng)氣(qi)(qi)(qi)孔。上(shang)引的(de)含氣(qi)(qi)(qi)量少時(shi),析出(chu)(chu)(chu)(chu)的(de)氫(qing)存在(zai)(zai)于(yu)晶(jing)界處,形成(cheng)疏松;含氣(qi)(qi)(qi)量多時(shi),則(ze)聚集成(cheng)氣(qi)(qi)(qi)孔,因此,氣(qi)(qi)(qi)孔和疏松是(shi)氫(qing)氣(qi)(qi)(qi)和水蒸氣(qi)(qi)(qi)兩者形成(cheng)的(de)。
氫來(lai)源于上(shang)引生產過程中的各個工(gong)藝環節,如(ru)原料電(dian)解銅(tong)(tong)(tong)的“銅(tong)(tong)(tong)綠(lv)”、輔(fu)料木(mu)炭**、氣(qi)候環境(jing)**、石墨結晶器未干燥(zao)等。因此,熔化爐中的銅(tong)(tong)(tong)液表面應覆(fu)蓋經烘烤(kao)的木(mu)炭,電(dian)解銅(tong)(tong)(tong)應盡量去除“銅(tong)(tong)(tong)綠(lv)”、“銅(tong)(tong)(tong)豆”“耳(er)朵(duo)”,對提(ti)高無(wu)氧銅(tong)(tong)(tong)桿質量非(fei)常重要。
在連鑄連軋工藝中(zhong),往往采用適度控(kong)制氧(yang)含量來控(kong)制氫。Cu2O+ H2= 2Cu+ H2O
由于銅(tong)液(ye)在鑄造過(guo)程中是自下而(er)(er)上(shang)結晶,銅(tong)液(ye)中的(de)氧和氫所(suo)產生的(de)水蒸氣很容(rong)易上(shang)浮跑(pao)出,銅(tong)液(ye)中的(de)氫大部分能被有(you)效去除,因而(er)(er)對(dui)銅(tong)桿的(de)影響較小(xiao)。
二、表面質量
在生產(chan)(chan)電磁線等(deng)產(chan)(chan)品的(de)(de)過程(cheng)中(zhong),對銅桿(gan)的(de)(de)表面質量也需提(ti)出要求。需要拉(la)制后的(de)(de)銅絲表面無毛刺、銅粉少、無油(you)污(wu)。并(bing)通過扭轉試驗測量表面銅粉的(de)(de)質量和扭轉后觀察銅桿(gan)的(de)(de)復原情況來判(pan)定(ding)其好(hao)壞。
在連鑄(zhu)連軋(ya)過程(cheng)中,從鑄(zhu)造(zao)到軋(ya)制前,溫度(du)高,完全暴露于(yu)空氣中,使鑄(zhu)坯表(biao)面(mian)形成(cheng)較厚(hou)的(de)氧化層(ceng),在軋(ya)制過程(cheng)中,隨(sui)著軋(ya)輥的(de)轉動,氧化物(wu)顆粒軋(ya)入(ru)銅線表(biao)面(mian)。由于(yu)氧化亞(ya)銅是(shi)高熔點脆(cui)性化合物(wu),對于(yu)軋(ya)入(ru)較深的(de)氧化亞(ya)銅,當成(cheng)條狀的(de)聚集(ji)物(wu)遇模具(ju)拉伸時,就(jiu)會是(shi)銅桿外表(biao)面(mian)產生毛刺,給后續的(de)涂(tu)漆造(zao)成(cheng)麻煩。
而上(shang)引連鑄工藝(yi)制造的無(wu)氧(yang)銅(tong)桿,由于鑄造和冷卻完全與氧(yang)隔絕(jue),后續亦無(wu)熱軋(ya)過程(cheng),銅(tong)桿表面無(wu)軋(ya)入表面的氧(yang)化(hua)物,質(zhi)量較好,拉制后銅(tong)粉少,上(shang)述問題較少存(cun)在。
無氧銅桿也(ye)分進口(kou)設(she)(she)(she)備做的(de)(de)(de)和國產(chan)(chan)(chan)設(she)(she)(she)備做的(de)(de)(de),但(dan)目前進口(kou)產(chan)(chan)(chan)品已無明顯優(you)勢(shi),銅桿產(chan)(chan)(chan)品出(chu)來后區別不是(shi)很大(da),只要銅板(ban)選的(de)(de)(de)好(hao),生產(chan)(chan)(chan)控(kong)制比(bi)較穩定,國產(chan)(chan)(chan)設(she)(she)(she)備也(ye)能產(chan)(chan)(chan)出(chu)可拉伸0.05的(de)(de)(de)銅桿.進口(kou)設(she)(she)(she)備一般(ban)是(shi)芬蘭(lan)奧托昆(kun)普的(de)(de)(de)設(she)(she)(she)備,國產(chan)(chan)(chan)設(she)(she)(she)備最好(hao)的(de)(de)(de)應(ying)該(gai)是(shi)上(shang)海的(de)(de)(de)海軍廠(chang)的(de)(de)(de)了,生產(chan)(chan)(chan)時間(jian)最長,軍工企業,質量可靠。
低氧銅桿(gan)進口(kou)設(she)備國(guo)(guo)(guo)際主要有(you)兩種,一種是(shi)(shi)美國(guo)(guo)(guo)南線設(she)備,英文是(shi)(shi)SOUTHWIRE,國(guo)(guo)(guo)內廠(chang)家是(shi)(shi)南京(jing)華新,江西銅業,另一種是(shi)(shi)德國(guo)(guo)(guo)CONTIROD設(she)備,國(guo)(guo)(guo)內廠(chang)家是(shi)(shi)常(chang)州金(jin)源,天津大無(wu)縫(feng)。
無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)及低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)從含氧(yang)(yang)(yang)(yang)(yang)量(liang)上容(rong)易(yi)區別,無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)是(shi)含氧(yang)(yang)(yang)(yang)(yang)量(liang)在(zai)(zai)10-20個(ge)PPM以下(xia)(xia),但目(mu)前有的(de)廠家只能做到(dao)50個(ge)PPM以下(xia)(xia).低(di)(di)氧(yang)(yang)(yang)(yang)(yang)銅(tong)桿(gan)在(zai)(zai) 200-400個(ge)PPM,好的(de)桿(gan)子一般含氧(yang)(yang)(yang)(yang)(yang)量(liang)控(kong)制在(zai)(zai)250個(ge)PPM左右,無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)桿(gan)一般采取(qu)的(de)是(shi)上引(yin)法,低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)是(shi)連鑄(zhu)連軋,兩種產品相對而(er)言低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)對漆(qi)包線(xian)性 能更適應些,如(ru)(ru)柔(rou)軟性,回彈(dan)角,繞線(xian)性能.但低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)對拉絲(si)條件(jian)(jian)相對要苛刻些,同(tong)樣拉伸0.2的(de)細(xi)絲(si),如(ru)(ru)果伸線(xian)條件(jian)(jian)不(bu)(bu)好,普(pu)通(tong)的(de)無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)桿(gan)可拉而(er)好的(de)低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)就(jiu)斷 線(xian),但如(ru)(ru)果放在(zai)(zai)好的(de)伸線(xian)條件(jian)(jian),同(tong)樣的(de)桿(gan)子,低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)說不(bu)(bu)定就(jiu)能拉到(dao)雙零五,而(er)普(pu)通(tong)無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)桿(gan)最多只能拉伸到(dao)0.1而(er)已,當然做的(de)最細(xi)的(de)如(ru)(ru)雙零二卻非得依靠(kao)進口的(de) 無(wu)(wu)氧(yang)(yang)(yang)(yang)(yang)銅(tong)桿(gan)了(le).目(mu)前有企業嘗試用(yong)剝皮(pi)的(de)方式來處理低(di)(di)氧(yang)(yang)(yang)(yang)(yang)桿(gan)來伸0.03線(xian).但有關這方面的(de)內容(rong)我還不(bu)(bu)是(shi)很(hen)清楚。
音響線一般反而喜歡用(yong)無(wu)氧桿(gan)(gan),這和無(wu)氧桿(gan)(gan)是(shi)單晶銅,低(di)氧桿(gan)(gan)是(shi)多(duo)晶銅有(you)關。
氧銅(tong)桿和無氧銅(tong)桿由于制造(zao)方(fang)法(fa)的不同,致使存在差別,具有各自的特(te)點。
一(yi)、關(guan)于氧的吸入和脫(tuo)去(qu)以及(ji)它(ta)的存在狀態
生產銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)陰(yin)極銅(tong)(tong)(tong)的(de)(de)(de)含氧(yang)(yang)(yang)量(liang)一(yi)(yi)般在(zai)(zai)10—50ppm,在(zai)(zai)常(chang)(chang)溫下氧(yang)(yang)(yang)在(zai)(zai)銅(tong)(tong)(tong)中(zhong)(zhong)的(de)(de)(de)固溶度約(yue)2ppm。低(di)(di)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)的(de)(de)(de)含氧(yang)(yang)(yang)量(liang)一(yi)(yi)般在(zai)(zai)200(175)—400(450)ppm,因此氧(yang)(yang)(yang)的(de)(de)(de)進(jin)入(ru)是在(zai)(zai)銅(tong)(tong)(tong)的(de)(de)(de)液(ye)態下吸入(ru)的(de)(de)(de),而(er)上引(yin)法無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則(ze)相反,氧(yang)(yang)(yang)在(zai)(zai)液(ye)態銅(tong)(tong)(tong)下保持相當時間(jian)后,被(bei)還原而(er)脫去,通(tong)常(chang)(chang)這(zhe)種(zhong)桿(gan)(gan)的(de)(de)(de)含氧(yang)(yang)(yang)量(liang)都在(zai)(zai)10—50ppm以下,最(zui)低(di)(di)可達1-2ppm,從組(zu)織(zhi)上看,低(di)(di)氧(yang)(yang)(yang)銅(tong)(tong)(tong)中(zhong)(zhong)的(de)(de)(de)氧(yang)(yang)(yang),以氧(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(dui)低(di)(di)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)而(er)言(yan)可以說是常(chang)(chang)見的(de)(de)(de)但對(dui)無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)則(ze)很(hen)少(shao)見。氧(yang)(yang)(yang)化銅(tong)(tong)(tong)以夾雜(za)形式在(zai)(zai)晶(jing)界出現對(dui)材料的(de)(de)(de)韌(ren)性產生負面影響。而(er)無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)中(zhong)(zhong)的(de)(de)(de)氧(yang)(yang)(yang)很(hen)低(di)(di),所以這(zhe)種(zhong)銅(tong)(tong)(tong)的(de)(de)(de)組(zu)織(zhi)是均勻的(de)(de)(de)單(dan)相組(zu)織(zhi)對(dui)韌(ren)性有利。在(zai)(zai)無(wu)(wu)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)中(zhong)(zhong)的(de)(de)(de)多(duo)孔性是不常(chang)(chang)見的(de)(de)(de),而(er)在(zai)(zai)低(di)(di)氧(yang)(yang)(yang)銅(tong)(tong)(tong)桿(gan)(gan)中(zhong)(zhong)則(ze)是常(chang)(chang)見的(de)(de)(de)一(yi)(yi)種(zhong)缺陷。
二、熱軋組(zu)織和鑄造組(zu)織的區別
低氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)由于經(jing)過熱軋,所以(yi)其(qi)組織(zhi)(zhi)(zhi)屬熱加(jia)工組織(zhi)(zhi)(zhi),原(yuan)來的(de)(de)(de)鑄(zhu)造(zao)組織(zhi)(zhi)(zhi)已經(jing)破碎,在(zai)(zai)(zai)8mm的(de)(de)(de)桿(gan)時已有(you)再(zai)結(jie)晶(jing)的(de)(de)(de)形式(shi)出(chu)現,而無(wu)氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)屬鑄(zhu)造(zao)組織(zhi)(zhi)(zhi),晶(jing)粒粗大,這(zhe)是(shi)為(wei)什么,無(wu)氧(yang)(yang)(yang)銅(tong)(tong)的(de)(de)(de)再(zai)結(jie)晶(jing)溫度較高(gao),需(xu)要較高(gao)退(tui)火(huo)(huo)溫度的(de)(de)(de)固有(you)原(yuan)因(yin)(yin)。這(zhe)是(shi)因(yin)(yin)為(wei),再(zai)結(jie)晶(jing)發生在(zai)(zai)(zai)晶(jing)粒邊(bian)界(jie)附(fu)近,無(wu)氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)組織(zhi)(zhi)(zhi)晶(jing)粒粗大,晶(jing)粒尺(chi)寸甚至能達幾個毫米,因(yin)(yin)而晶(jing)粒邊(bian)界(jie)少,即使通過拉制變形,但晶(jing)粒邊(bian)界(jie)相對低氧(yang)(yang)(yang)銅(tong)(tong)桿(gan)還是(shi)較少,所以(yi)需(xu)要較高(gao)的(de)(de)(de)退(tui)火(huo)(huo)功率。對無(wu)氧(yang)(yang)(yang)銅(tong)(tong)成(cheng)功的(de)(de)(de)退(tui)火(huo)(huo)要求是(shi):由桿(gan)經(jing)拉制,但尚未鑄(zhu)造(zao)組織(zhi)(zhi)(zhi)的(de)(de)(de)線時的(de)(de)(de)第一次(ci)退(tui)火(huo)(huo),其(qi)退(tui)火(huo)(huo)功率應比同樣(yang)情(qing)況的(de)(de)(de)低氧(yang)(yang)(yang)銅(tong)(tong)高(gao)10——15%。經(jing)繼續拉制,在(zai)(zai)(zai)以(yi)后階段的(de)(de)(de)退(tui)火(huo)(huo)功率應留(liu)有(you)足夠的(de)(de)(de)余量(liang)和對低氧(yang)(yang)(yang)銅(tong)(tong)和無(wu)氧(yang)(yang)(yang)銅(tong)(tong)切實區(qu)別執(zhi)行不(bu)同的(de)(de)(de)退(tui)火(huo)(huo)工藝,以(yi)保證在(zai)(zai)(zai)制品(pin)和成(cheng)品(pin)導線的(de)(de)(de)柔軟性。
三、夾雜,氧含(han)量波動,表面氧化(hua)物和可能(neng)存在的(de)熱軋缺陷的(de)差別
無氧銅(tong)桿的(de)(de)可拉性(xing)在(zai)(zai)所(suo)有(you)(you)線(xian)(xian)徑里與(yu)低氧銅(tong)桿相比(bi)都是優越的(de)(de),除(chu)上(shang)述組織原(yuan)因(yin)外,無氧銅(tong)桿夾雜少(shao),含氧量穩定(ding)(ding),無熱軋(ya)可能(neng)(neng)產(chan)生的(de)(de)缺(que)陷,桿表(biao)氧化(hua)(hua)物厚度(du)可達≤15A。在(zai)(zai)連鑄連軋(ya)生產(chan)過程(cheng)中(zhong)如果工藝不(bu)穩定(ding)(ding),對氧監控不(bu)嚴,含氧量不(bu)穩定(ding)(ding)將直接(jie)(jie)影(ying)響桿的(de)(de)性(xing)能(neng)(neng)。如果桿的(de)(de)表(biao)面氧化(hua)(hua)物能(neng)(neng)在(zai)(zai)后工序的(de)(de)連續(xu)清(qing)洗中(zhong)得以彌補外,但比(bi)較麻(ma)煩的(de)(de)是有(you)(you)相當多的(de)(de)氧化(hua)(hua)物存在(zai)(zai)于“皮下”,對拉線(xian)(xian)斷線(xian)(xian)影(ying)響更直接(jie)(jie),故而(er)在(zai)(zai)拉制(zhi)微細線(xian)(xian),超微細線(xian)(xian)時,為了(le)減少(shao)斷線(xian)(xian),有(you)(you)時要對銅(tong)桿采(cai)取(qu)不(bu)得已的(de)(de)辦法(fa)——剝皮,甚至二次剝皮的(de)(de)原(yuan)因(yin)所(suo)在(zai)(zai),目的(de)(de)要除(chu)去皮下氧化(hua)(hua)物。
四、低氧(yang)銅(tong)桿和無氧(yang)銅(tong)桿的(de)韌性有(you)差(cha)別(bie)
兩(liang)者(zhe)都可以拉到(dao)0.015mm,但在(zai)低溫超導線中的低溫級無氧銅,其細(xi)絲間的間距只有(you)0.001mm.
五、從制(zhi)桿的(de)原材(cai)料(liao)到制(zhi)線的(de)經濟性有差別。
制(zhi)(zhi)造無(wu)氧(yang)(yang)銅(tong)桿要求質量較(jiao)(jiao)高的原(yuan)材料。一般,拉(la)制(zhi)(zhi)直徑(jing)>1mm的銅(tong)線(xian)時(shi),低氧(yang)(yang)銅(tong)桿的優(you)點比較(jiao)(jiao)明顯,而無(wu)氧(yang)(yang)銅(tong)桿顯得更為優(you)越(yue)的是(shi)拉(la)制(zhi)(zhi)直徑(jing)<0.5mm的銅(tong)線(xian)。
六、低(di)氧(yang)(yang)銅(tong)桿的制(zhi)線工藝與無氧(yang)(yang)銅(tong)桿的有所不(bu)同(tong)。
低(di)氧銅桿(gan)的(de)制(zhi)線(xian)工藝不能照搬(ban)到無氧銅桿(gan)的(de)制(zhi)線(xian)工藝上(shang)來(lai),至少兩者的(de)退火(huo)工藝是(shi)不同的(de)。因為線(xian)的(de)柔軟性深受材料(liao)成份和制(zhi)桿(gan),制(zhi)線(xian)和退火(huo)工藝的(de)影響,不能簡單地說低(di)氧銅或(huo)無氧銅誰軟誰硬。