一、研究的背景與問題

稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)是(shi)我(wo)國(guo)特有的(de)(de)優(you)(you)勢資(zi)(zi)源(yuan)(yuan)，俗稱(cheng)工(gong)(gong)業(ye)(ye)維生(sheng)素。白云(yun)鄂博稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)儲量(liang)約(yue)(yue)占全國(guo)的(de)(de)83%，以(yi)鑭、鈰(shi)輕(qing)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)為(wei)主(zhu)，但其(qi)利(li)(li)用(yong)(yong)(yong)(yong)率不(bu)(bu)足20%，造成資(zi)(zi)源(yuan)(yuan)浪費，急需(xu)找到(dao)應(ying)用(yong)(yong)(yong)(yong)出口，解決稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)積壓難題，實現稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)資(zi)(zi)源(yuan)(yuan)平衡(heng)利(li)(li)用(yong)(yong)(yong)(yong)。稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)元素具有獨特的(de)(de)電子層結構(gou)和(he)(he)大(da)原子尺寸，微(wei)量(liang)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)元素就能夠顯(xian)著提升材料(liao)的(de)(de)品質和(he)(he)性能。研(yan)究表明(ming)，鋼(gang)(gang)中(zhong)(zhong)應(ying)用(yong)(yong)(yong)(yong)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)后，可以(yi)起(qi)到(dao)細(xi)化(hua)變質夾雜、深(shen)度(du)凈(jing)化(hua)鋼(gang)(gang)液和(he)(he)強(qiang)烈微(wei)合金(jin)(jin)化(hua)作用(yong)(yong)(yong)(yong)，顯(xian)著提高鋼(gang)(gang)的(de)(de)韌、塑性和(he)(he)疲勞(lao)壽(shou)命(ming)，使鋼(gang)(gang)更加(jia)(jia)強(qiang)韌、耐(nai)熱、耐(nai)磨、耐(nai)蝕。鑭、鈰(shi)輕(qing)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)的(de)(de)開采和(he)(he)制備(bei)成本很(hen)低，電解分離后每噸(dun)(dun)價(jia)格不(bu)(bu)超過(guo)10萬(wan)元，低于鎳(nie)、鉬、鈮(ni)等貴金(jin)(jin)屬，物美價(jia)廉。稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)的(de)(de)加(jia)(jia)入(ru)量(liang)大(da)約(yue)(yue)為(wei)噸(dun)(dun)鋼(gang)(gang)0.2～0.4公斤(jin)，真正起(qi)到(dao)了(le)(le)四兩撥千(qian)斤(jin)的(de)(de)作用(yong)(yong)(yong)(yong)！采用(yong)(yong)(yong)(yong)鑭、鈰(shi)輕(qing)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)提升鋼(gang)(gang)鐵(tie)質量(liang)，是(shi)一(yi)條引(yin)領鋼(gang)(gang)鐵(tie)行(xing)(xing)(xing)業(ye)(ye)轉型(xing)升級的(de)(de)有效途徑。國(guo)際上(shang)，發達國(guo)家由(you)于沒(mei)有稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)資(zi)(zi)源(yuan)(yuan)優(you)(you)勢，僅在(zai)特殊鋼(gang)(gang)中(zhong)(zhong)應(ying)用(yong)(yong)(yong)(yong)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)，歐盟兩年(nian)(nian)前啟動了(le)(le)替代稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)的(de)(de)冶(ye)金(jin)(jin)工(gong)(gong)程(cheng)(cheng)項目，抓緊研(yan)究如何在(zai)冶(ye)金(jin)(jin)過(guo)程(cheng)(cheng)減少對稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)的(de)(de)依賴。美國(guo)在(zai)鋼(gang)(gang)鐵(tie)產(chan)(chan)量(liang)達到(dao)1億噸(dun)(dun)時，其(qi)中(zhong)(zhong)800萬(wan)噸(dun)(dun)鋼(gang)(gang)為(wei)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)鋼(gang)(gang)。我(wo)國(guo)是(shi)世界第一(yi)產(chan)(chan)鋼(gang)(gang)大(da)國(guo)，而(er)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)又是(shi)我(wo)國(guo)的(de)(de)優(you)(you)勢資(zi)(zi)源(yuan)(yuan)，卻沒(mei)有在(zai)國(guo)產(chan)(chan)鋼(gang)(gang)中(zhong)(zhong)大(da)批(pi)量(liang)應(ying)用(yong)(yong)(yong)(yong)，實在(zai)是(shi)一(yi)大(da)憾(han)事(shi)！高峰時，中(zhong)(zhong)國(guo)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)鋼(gang)(gang)的(de)(de)年(nian)(nian)產(chan)(chan)量(liang)僅約(yue)(yue)100萬(wan)噸(dun)(dun)。鋼(gang)(gang)鐵(tie)行(xing)(xing)(xing)業(ye)(ye)達成的(de)(de)共識(shi)是(shi)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)作用(yong)(yong)(yong)(yong)明(ming)顯(xian)但是(shi)沒(mei)有用(yong)(yong)(yong)(yong)好(hao)。稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)鋼(gang)(gang)工(gong)(gong)業(ye)(ye)化(hua)應(ying)用(yong)(yong)(yong)(yong)有兩大(da)瓶(ping)頸問題一(yi)直(zhi)沒(mei)有解決：一(yi)是(shi)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)加(jia)(jia)入(ru)鋼(gang)(gang)水中(zhong)(zhong)堵塞澆注系統，連鑄過(guo)程(cheng)(cheng)被迫中(zhong)(zhong)斷(duan)，嚴重影響(xiang)工(gong)(gong)藝順行(xing)(xing)(xing)；二(er)是(shi)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)加(jia)(jia)入(ru)后，容易(yi)形(xing)成大(da)尺寸、高密度(du)的(de)(de)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)夾雜物，導致鋼(gang)(gang)的(de)(de)性能時好(hao)時壞，不(bu)(bu)穩定(ding)。上(shang)述問題一(yi)直(zhi)懸而(er)未決，嚴重制約(yue)(yue)了(le)(le)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)鋼(gang)(gang)的(de)(de)應(ying)用(yong)(yong)(yong)(yong)。除極個別鋼(gang)(gang)種外，中(zhong)(zhong)國(guo)鋼(gang)(gang)鐵(tie)行(xing)(xing)(xing)業(ye)(ye)稀(xi)(xi)(xi)(xi)(xi)土(tu)(tu)應(ying)用(yong)(yong)(yong)(yong)基(ji)本處于停(ting)滯狀態。

　　二、解決(jue)問題的(de)(de)(de)(de)(de)(de)思路與技(ji)術(shu)(shu)方(fang)案(an)中(zhong)國(guo)科學(xue)院(yuan)金(jin)(jin)(jin)屬(shu)研(yan)究所自建所之初就部署了(le)(le)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)研(yan)究方(fang)向(xiang)。2007年(nian)以(yi)來開展(zhan)新一(yi)輪稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)研(yan)究，經過(guo)多年(nian)持續攻關(guan)(guan)(guan)(guan)，深入(ru)生產企業(ye)進行實(shi)(shi)地考察，通過(guo)大量(liang)(liang)實(shi)(shi)驗(yan)室研(yan)究和(he)(he)工程化(hua)(hua)(hua)試驗(yan)，揭示了(le)(le)純(chun)(chun)(chun)凈(jing)(jing)度(du)尤(you)其是(shi)(shi)氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)對稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)性(xing)(xing)能提(ti)升(sheng)的(de)(de)(de)(de)(de)(de)決(jue)定性(xing)(xing)作(zuo)用(yong)，控(kong)制(zhi)氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)是(shi)(shi)實(shi)(shi)現(xian)高(gao)(gao)品質特(te)殊鋼(gang)(gang)“高(gao)(gao)純(chun)(chun)(chun)、均質”的(de)(de)(de)(de)(de)(de)關(guan)(guan)(guan)(guan)鍵。受此(ci)啟發(fa)，中(zhong)國(guo)科學(xue)院(yuan)金(jin)(jin)(jin)屬(shu)研(yan)究所發(fa)現(xian)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)本身的(de)(de)(de)(de)(de)(de)純(chun)(chun)(chun)凈(jing)(jing)度(du)和(he)(he)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)加(jia)入(ru)前(qian)鋼(gang)(gang)液的(de)(de)(de)(de)(de)(de)純(chun)(chun)(chun)凈(jing)(jing)度(du)，是(shi)(shi)影響稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)在(zai)鋼(gang)(gang)中(zhong)發(fa)揮有益作(zuo)用(yong)和(he)(he)工業(ye)化(hua)(hua)(hua)生產工藝(yi)不穩(wen)定的(de)(de)(de)(de)(de)(de)關(guan)(guan)(guan)(guan)鍵因(yin)素(su)。研(yan)究結果表(biao)明，稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)中(zhong)即使(shi)含(han)(han)有幾百ppm少量(liang)(liang)的(de)(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)，也(ye)足(zu)以(yi)使(shi)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)在(zai)鋼(gang)(gang)中(zhong)的(de)(de)(de)(de)(de)(de)作(zuo)用(yong)由正變負，而(er)部分商業(ye)純(chun)(chun)(chun)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)中(zhong)的(de)(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)甚至高(gao)(gao)達1000ppm以(yi)上。因(yin)此(ci)，稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)與鋼(gang)(gang)水雙純(chun)(chun)(chun)凈(jing)(jing)雙低(di)(di)(di)氧(yang)(yang)(yang)(yang)是(shi)(shi)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)獲得穩(wen)定應用(yong)的(de)(de)(de)(de)(de)(de)前(qian)提(ti)和(he)(he)基礎。基于(yu)此(ci)，中(zhong)國(guo)科學(xue)院(yuan)金(jin)(jin)(jin)屬(shu)研(yan)究所研(yan)發(fa)了(le)(le)高(gao)(gao)純(chun)(chun)(chun)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)制(zhi)備(bei)關(guan)(guan)(guan)(guan)鍵技(ji)術(shu)(shu)與鋼(gang)(gang)水純(chun)(chun)(chun)凈(jing)(jing)度(du)控(kong)制(zhi)工藝(yi)，通過(guo)控(kong)制(zhi)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)原料中(zhong)的(de)(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)、稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)加(jia)入(ru)前(qian)鋼(gang)(gang)水中(zhong)的(de)(de)(de)(de)(de)(de)氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)和(he)(he)雜(za)(za)質元(yuan)素(su)，突破了(le)(le)生產工藝(yi)不能順行和(he)(he)性(xing)(xing)能不穩(wen)定兩大難題，成功(gong)細化(hua)(hua)(hua)夾雜(za)(za)物到亞微(wei)米尺度(du)，制(zhi)備(bei)出超高(gao)(gao)潔凈(jing)(jing)度(du)亞微(wei)米夾雜(za)(za)物的(de)(de)(de)(de)(de)(de)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)。稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)共(gong)性(xing)(xing)關(guan)(guan)(guan)(guan)鍵技(ji)術(shu)(shu)路線(xian)示意圖如(ru)圖1所示。中(zhong)科院(yuan)金(jin)(jin)(jin)屬(shu)所通過(guo)優(you)化(hua)(hua)(hua)設計爐體結構、優(you)化(hua)(hua)(hua)調整工藝(yi)參數(shu)、防氧(yang)(yang)(yang)(yang)化(hua)(hua)(hua)澆(jiao)注(zhu)和(he)(he)防氧(yang)(yang)(yang)(yang)化(hua)(hua)(hua)儲(chu)運等(deng)方(fang)式(shi)實(shi)(shi)現(xian)了(le)(le)高(gao)(gao)純(chun)(chun)(chun)低(di)(di)(di)氧(yang)(yang)(yang)(yang)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)制(zhi)備(bei)，稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)金(jin)(jin)(jin)屬(shu)的(de)(de)(de)(de)(de)(de)全氧(yang)(yang)(yang)(yang)含(han)(han)量(liang)(liang)低(di)(di)(di)于(yu)100ppm；同時，通過(guo)采取(qu)低(di)(di)(di)氧(yang)(yang)(yang)(yang)純(chun)(chun)(chun)凈(jing)(jing)化(hua)(hua)(hua)冶煉、創新稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)加(jia)入(ru)工藝(yi)、控(kong)氧(yang)(yang)(yang)(yang)自動(dong)化(hua)(hua)(hua)澆(jiao)注(zhu)、低(di)(di)(di)偏(pian)析微(wei)缺陷控(kong)制(zhi)等(deng)手段實(shi)(shi)現(xian)了(le)(le)全流程低(di)(di)(di)氧(yang)(yang)(yang)(yang)鋼(gang)(gang)水純(chun)(chun)(chun)凈(jing)(jing)度(du)控(kong)制(zhi)，能夠保障千噸級稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)連鑄生產順行，從而(er)形成了(le)(le)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)鋼(gang)(gang)工業(ye)化(hua)(hua)(hua)應用(yong)共(gong)性(xing)(xing)關(guan)(guan)(guan)(guan)鍵技(ji)術(shu)(shu)，實(shi)(shi)現(xian)了(le)(le)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)(tu)(tu)(tu)(tu)(tu)在(zai)鋼(gang)(gang)中(zhong)工業(ye)化(hua)(hua)(hua)應用(yong)的(de)(de)(de)(de)(de)(de)實(shi)(shi)質性(xing)(xing)突破。

　　圖(tu)(tu)1 稀土鋼(gang)共性關(guan)鍵(jian)技術路線示意圖(tu)(tu)

　　二、主要創新性成果中國科學院金屬研究所發現，稀土金屬可以將鋼中Al₂O₃和(he)MnS兩類典型的(de)有害(hai)夾(jia)雜(za)物變質(zhi)(zhi)(zhi)成為(wei)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)反應產(chan)物。借(jie)助熱力(li)(li)學與(yu)動力(li)(li)學機制(zhi)，可以使(shi)有害(hai)夾(jia)雜(za)變質(zhi)(zhi)(zhi)成尺寸細小、硬(ying)度(du)與(yu)鋼(gang)(gang)基體接近、彌(mi)散分(fen)布的(de)團球狀稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)氧(yang)(yang)硫化(hua)(hua)物，從(cong)而大(da)幅(fu)度(du)提升特殊鋼(gang)(gang)的(de)韌(ren)塑(su)性與(yu)疲勞性能。同時，在(zai)低(di)氧(yang)(yang)純(chun)凈化(hua)(hua)條(tiao)(tiao)件(jian)下(xia)，鋼(gang)(gang)中加入高純(chun)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)，能夠進一步深脫氧(yang)(yang)，大(da)幅(fu)降低(di)夾(jia)雜(za)物總量，起到顯著細化(hua)(hua)、球化(hua)(hua)、變質(zhi)(zhi)(zhi)夾(jia)雜(za)的(de)作用(yong)(yong)。此外，在(zai)低(di)氧(yang)(yang)純(chun)凈化(hua)(hua)條(tiao)(tiao)件(jian)下(xia)，中國(guo)科學院(yuan)(yuan)金屬研(yan)究所還發現，稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)元素能夠以固溶態原(yuan)子形式，偏(pian)聚晶界、提高晶界結合力(li)(li)，或者(zhe)在(zai)晶內與(yu)空(kong)位形成穩定的(de)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)-空(kong)位對，從(cong)而影響(xiang)擴散。在(zai)低(di)氧(yang)(yang)純(chun)凈化(hua)(hua)冶煉(lian)、控(kong)氧(yang)(yang)自(zi)動化(hua)(hua)澆注、低(di)偏(pian)析微缺陷(xian)控(kong)制(zhi)等(deng)成套制(zhi)備(bei)技(ji)術(shu)(shu)的(de)基礎上(shang)，中國(guo)科學院(yuan)(yuan)金屬研(yan)究所突破了(le)高溫(wen)鋼(gang)(gang)液和(he)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)金屬的(de)“雙低(di)氧(yang)(yang)”控(kong)制(zhi)技(ji)術(shu)(shu)，開發了(le)全流程(cheng)控(kong)純(chun)的(de)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)添加技(ji)術(shu)(shu)，提出了(le)適用(yong)(yong)于冶金行業(ye)使(shi)用(yong)(yong)的(de)低(di)氧(yang)(yang)高純(chun)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)金屬技(ji)術(shu)(shu)條(tiao)(tiao)件(jian)，解決了(le)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)鋼(gang)(gang)工業(ye)化(hua)(hua)應用(yong)(yong)面臨“產(chan)品質(zhi)(zhi)(zhi)量不穩定”和(he)“生(sheng)產(chan)工藝不順(shun)行”的(de)技(ji)術(shu)(shu)瓶頸問題，為(wei)高品質(zhi)(zhi)(zhi)稀(xi)(xi)(xi)(xi)(xi)(xi)土(tu)鋼(gang)(gang)自(zi)主品牌(pai)研(yan)發及產(chan)業(ye)化(hua)(hua)奠定了(le)先決條(tiao)(tiao)件(jian)。 

　　四、應用情況與效果稀土鋼共性關鍵技術先后在國內十余家企業的軸承鋼、不銹鋼、齒輪鋼、模具鋼、重軌鋼、風電用鋼、汽車鋼等幾十個優特鋼品種上進行了批量試驗與應用，工藝穩定，效果顯著。高潔凈度稀土金屬在低氧鋼中加入使夾雜物總量減少50%以上，可以將大尺寸、不規則形狀的Al₂O₃和MnS兩類典型有害夾雜變質成為5μm以下的RE₂O₂S，形成硬度低、尺寸小、球形且均勻分布的稀土氧硫化物，且大多數RE₂O₂S尺寸介于亞微米級100～800nm，如圖2所示。利用上述技術制備的工業化稀土軸承鋼超高周疲勞壽命較國際先進水平提高一個數量級（圖3）、滾動接觸疲勞壽命提高40%。進一步的研究結果發現，稀土氧硫化物硬度小、與基體錯配度小，能夠協調變形，緩解應力集中，從而遲滯位錯的增殖、運動與重排，延遲疲勞裂紋萌生，如圖4所示。同時，稀土氧硫化物尺寸小，ΔK_I低，裂(lie)(lie)紋(wen)(wen)擴展驅動力小，擴展速度慢，因此還有利(li)于抑制裂(lie)(lie)紋(wen)(wen)擴展。

圖(tu)2 潔凈GCr15與(yu)RE-GCr15鋼中夾(jia)雜(za)物尺寸與(yu)形(xing)貌(a)潔凈GCr15; (b)RE-GCr15

　　圖3 超高周疲勞P-S-N曲(qu)線（10kHz）

圖4 疲勞斷口夾雜物毗鄰基體處位錯形貌(a)Al₂O₃; (b)RE₂O₂S

　　就不銹鋼中應用稀土而言，中國科學院金屬研究所前期與企業合作，在400系不銹鋼中進行稀土共性關鍵技術應用。工業化應用結果表明，鋼液中尺寸>10μm夾雜物由9個/cm²降低到3.5個/cm²；成品(pin)板材(cai)中(zhong)尺寸>5μm的夾雜物數量減少約50%，夾雜物平(ping)均尺寸由5.2μm降低到3.9μm，延伸率(lv)由20%提高(gao)到25%。稀(xi)土在(zai)不(bu)銹(xiu)鋼(gang)中(zhong)的應(ying)用具有普(pu)適性(xing)，可以(yi)(yi)提升不(bu)銹(xiu)鋼(gang)純凈(jing)度，提高(gao)耐(nai)蝕(shi)性(xing)與(yu)深(shen)沖性(xing)。此外(wai)，稀(xi)土鋼(gang)共性(xing)關鍵技術(shu)在(zai)其(qi)他品(pin)種鋼(gang)的工(gong)業化(hua)應(ying)用效果顯示(shi)，高(gao)純稀(xi)土金屬的加入能夠(gou)使優質碳素(su)結構鋼(gang)及(ji)橋梁鋼(gang)的韌塑性(xing)提高(gao)40%以(yi)(yi)上(shang)(shang)，重軌鋼(gang)疲勞壽命提高(gao)30%，模具鋼(gang)等向性(xing)達(da)到0.9以(yi)(yi)上(shang)(shang)的國際(ji)領先(xian)水平(ping)。中(zhong)國科學院金屬研究所實現了稀(xi)土合金鋼(gang)千噸(dun)以(yi)(yi)上(shang)(shang)連(lian)鑄的率(lv)先(xian)突破(po)，完全攻(gong)克(ke)了稀(xi)土在(zai)鋼(gang)中(zhong)進行大(da)規模工(gong)業化(hua)應(ying)用的瓶頸。 

　　來源：中(zhong)國科學院金屬研究所