20#精密鋼管批發零售

　　現貨充足,定制加工各種規格20#精密鋼管,發貨快,報價低,全國可發,我司專業生(sheng)產,歡(huan)迎咨(zi)詢(xun)~

　　20#精密鋼管熱處(chu)理工藝

　　精密鋼管前奏

　　真(zhen)空退(tui)火優質彈簧鋼(gang)(gang)(gang)(gang)、工具(ju)鋼(gang)(gang)(gang)(gang)、精(jing)密鋼(gang)(gang)(gang)(gang)管的絲材，不銹(xiu)鋼(gang)(gang)(gang)(gang)制品(pin)及鈦(tai)合(he)金材，作光(guang)亮退(tui)火均可采用(yong)真(zhen)空處理。退(tui)火溫(wen)度(du)愈(yu)低，則(ze)要(yao)求(qiu)真(zhen)空度(du)愈(yu)高(gao)。為(wei)防(fang)止(zhi)鉻的蒸發(fa)及加速熱傳導，一般采用(yong)載(zai)氣加熱(保溫(wen))法，并注意(yi)對不銹(xiu)鋼(gang)(gang)(gang)(gang)和鈦(tai)合(he)金不宜用(yong)氮而應采用(yong)氬氣。

　　精密鋼管過程

　　真(zhen)(zhen)空(kong)淬(cui)(cui)火(huo)(huo)(huo)真(zhen)(zhen)空(kong)淬(cui)(cui)火(huo)(huo)(huo)爐(lu)按(an)冷(leng)(leng)(leng)卻(que)方(fang)法(fa)分為(wei)油(you)(you)(you)(you)淬(cui)(cui)和(he)(he)氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)兩類，按(an)工(gong)(gong)(gong)(gong)位(wei)數分為(wei)單室(shi)(shi)式(shi)和(he)(he)雙室(shi)(shi)式(shi)，904山\畏嘲均(jun)屬周(zhou)期(qi)式(shi)作(zuo)業爐(lu)。真(zhen)(zhen)空(kong)油(you)(you)(you)(you)淬(cui)(cui)爐(lu)都是雙室(shi)(shi)的(de)(de)(de)(de)(de)，后(hou)(hou)室(shi)(shi)置(zhi)電加(jia)熱(re)元件，前室(shi)(shi)的(de)(de)(de)(de)(de)下(xia)方(fang)置(zhi)油(you)(you)(you)(you)槽。工(gong)(gong)(gong)(gong)件完(wan)成(cheng)加(jia)熱(re)、保(bao)溫(wen)(wen)后(hou)(hou)移入(ru)(ru)前室(shi)(shi)，關閉(bi)中(zhong)門后(hou)(hou)向前室(shi)(shi)充(chong)入(ru)(ru)惰(duo)性(xing)(xing)(xing)氣(qi)(qi)(qi)(qi)(qi)至大約(yue)2.66%26times;lO ～1.01%26times;10 Pa(200～760mm汞柱)，入(ru)(ru)油(you)(you)(you)(you)。油(you)(you)(you)(you)淬(cui)(cui)易引起(qi)工(gong)(gong)(gong)(gong)件表面(mian)變(bian)質。由于(yu)表面(mian)活性(xing)(xing)(xing)大，在(zai)(zai)(zai)短暫(zan)的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)(wen)油(you)(you)(you)(you)膜作(zuo)用(yong)(yong)(yong)下(xia)即可發(fa)生(sheng)顯著薄層滲碳，此(ci)外，碳黑(hei)和(he)(he)油(you)(you)(you)(you)在(zai)(zai)(zai)表面(mian)的(de)(de)(de)(de)(de)粘附(fu)對(dui)簡化熱(re)處(chu)(chu)理流程很不(bu)利。真(zhen)(zhen)空(kong)淬(cui)(cui)火(huo)(huo)(huo)技術(shu)的(de)(de)(de)(de)(de)發(fa)展(zhan)主(zhu)要(yao)在(zai)(zai)(zai)于(yu)研制性(xing)(xing)(xing)能(neng)優良、工(gong)(gong)(gong)(gong)位(wei)單一的(de)(de)(de)(de)(de)氣(qi)(qi)(qi)(qi)(qi)冷(leng)(leng)(leng)淬(cui)(cui)火(huo)(huo)(huo)爐(lu)。前述雙室(shi)(shi)式(shi)爐(lu)亦可用(yong)(yong)(yong)于(yu)氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)(在(zai)(zai)(zai)前室(shi)(shi)噴氣(qi)(qi)(qi)(qi)(qi)冷(leng)(leng)(leng)卻(que))，但雙工(gong)(gong)(gong)(gong)位(wei)式(shi)的(de)(de)(de)(de)(de)操作(zuo)使大批量裝爐(lu)的(de)(de)(de)(de)(de)生(sheng)產發(fa)生(sheng)困難，也(ye)易在(zai)(zai)(zai)高(gao)(gao)溫(wen)(wen)移動中(zhong)引起(qi)工(gong)(gong)(gong)(gong)件變(bian)形或(huo)改變(bian)工(gong)(gong)(gong)(gong)件方(fang)位(wei)增加(jia)淬(cui)(cui)火(huo)(huo)(huo)變(bian)形。單一工(gong)(gong)(gong)(gong)位(wei)的(de)(de)(de)(de)(de)氣(qi)(qi)(qi)(qi)(qi)冷(leng)(leng)(leng)淬(cui)(cui)火(huo)(huo)(huo)爐(lu)是在(zai)(zai)(zai)加(jia)熱(re)保(bao)溫(wen)(wen)完(wan)成(cheng)后(hou)(hou)在(zai)(zai)(zai)加(jia)熱(re)室(shi)(shi)內噴氣(qi)(qi)(qi)(qi)(qi)冷(leng)(leng)(leng)卻(que)。氣(qi)(qi)(qi)(qi)(qi)冷(leng)(leng)(leng)的(de)(de)(de)(de)(de)冷(leng)(leng)(leng)速不(bu)如油(you)(you)(you)(you)冷(leng)(leng)(leng)快，也(ye)低于(yu)傳(chuan)統淬(cui)(cui)火(huo)(huo)(huo)法(fa)中(zhong)的(de)(de)(de)(de)(de)熔鹽等溫(wen)(wen)、分級淬(cui)(cui)火(huo)(huo)(huo)。因而(er)，不(bu)斷(duan)提(ti)高(gao)(gao)噴冷(leng)(leng)(leng)室(shi)(shi)壓(ya)(ya)(ya)力(li)(li)，增大流量，以(yi)及(ji)采(cai)(cai)用(yong)(yong)(yong)摩爾質量比(bi)氮(dan)和(he)(he)氬(ya)小的(de)(de)(de)(de)(de)惰(duo)性(xing)(xing)(xing)氣(qi)(qi)(qi)(qi)(qi)體氦和(he)(he)氫，是當今真(zhen)(zhen)空(kong)淬(cui)(cui)火(huo)(huo)(huo)技術(shu)發(fa)展(zhan)的(de)(de)(de)(de)(de)主(zhu)流。70年代后(hou)(hou)期(qi)將氮(dan)氣(qi)(qi)(qi)(qi)(qi)噴冷(leng)(leng)(leng)的(de)(de)(de)(de)(de)壓(ya)(ya)(ya)力(li)(li)從(1～2)%26times;10Pa提(ti)高(gao)(gao)到(5～6)%26times;10Pa，使冷(leng)(leng)(leng)卻(que)能(neng)力(li)(li)接(jie)近于(yu)常壓(ya)(ya)(ya)下(xia)的(de)(de)(de)(de)(de)油(you)(you)(you)(you)冷(leng)(leng)(leng)。80年代中(zhong)期(qi)出現超高(gao)(gao)壓(ya)(ya)(ya)氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)，用(yong)(yong)(yong)(10～20)%26times;10Pa的(de)(de)(de)(de)(de)氦，冷(leng)(leng)(leng)卻(que)能(neng)力(li)(li)等于(yu)或(huo)略(lve)高(gao)(gao)于(yu)油(you)(you)(you)(you)淬(cui)(cui)，已(yi)(yi)進入(ru)(ru)工(gong)(gong)(gong)(gong)業實用(yong)(yong)(yong)。90年代初采(cai)(cai)用(yong)(yong)(yong)40%26times;10Pa的(de)(de)(de)(de)(de)氫氣(qi)(qi)(qi)(qi)(qi)，接(jie)近水淬(cui)(cui)的(de)(de)(de)(de)(de)冷(leng)(leng)(leng)卻(que)能(neng)力(li)(li)，尚處(chu)(chu)于(yu)起(qi)步階段。工(gong)(gong)(gong)(gong)業發(fa)達國(guo)家(jia)已(yi)(yi)進展(zhan)到以(yi)高(gao)(gao)壓(ya)(ya)(ya)(5～6)%26times;10。Pa氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)為(wei)主(zhu)體，而(er)中(zhong)國(guo)產氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)一些金屬的(de)(de)(de)(de)(de)蒸氣(qi)(qi)(qi)(qi)(qi)壓(ya)(ya)(ya)(理論值)與溫(wen)(wen)度的(de)(de)(de)(de)(de)關系則尚處(chu)(chu)于(yu)一般(ban)加(jia)壓(ya)(ya)(ya)氣(qi)(qi)(qi)(qi)(qi)淬(cui)(cui)(2%26times;10Pa)型階段。

　　結果真(zhen)空滲(shen)(shen)(shen)碳為(wei)真(zhen)空滲(shen)(shen)(shen)碳一淬火(huo)(huo)工藝曲(qu)線。在(zai)真(zhen)空中(zhong)加熱到滲(shen)(shen)(shen)碳溫(wen)(wen)(wen)度(du)并保溫(wen)(wen)(wen)使表面(mian)凈化(hua)、活化(hua)之后(hou)，通(tong)入(ru)(ru)稀薄滲(shen)(shen)(shen)碳富化(hua)氣(qi)(qi)(qi)(見控制氣(qi)(qi)(qi)氛熱處理)，在(zai)大約(yue)1330Pa(10T0rr)負壓(ya)下(xia)進行(xing)(xing)滲(shen)(shen)(shen)入(ru)(ru)，然后(hou)停(ting)氣(qi)(qi)(qi)(降壓(ya))進行(xing)(xing)擴(kuo)散(san)。滲(shen)(shen)(shen)碳后(hou)的(de)精(jing)密(mi)鋼管(guan)淬火(huo)(huo)采(cai)(cai)用(yong)一次淬火(huo)(huo)法，即先停(ting)電，通(tong)氮(dan)(dan)冷(leng)(leng)卻工件(jian)至臨界點A，、以下(xia)，使內部(bu)發生相(xiang)變(bian)，再(zai)停(ting)氣(qi)(qi)(qi)、開(kai)泵，升溫(wen)(wen)(wen)到Ac1，～Accm之間(jian)。淬冷(leng)(leng)方(fang)法可(ke)(ke)采(cai)(cai)用(yong)氣(qi)(qi)(qi)冷(leng)(leng)或油冷(leng)(leng)。后(hou)者為(wei)奧氏(shi)體(ti)化(hua)后(hou)移入(ru)(ru)前(qian)室，充氮(dan)(dan)至常壓(ya)，入(ru)(ru)油。真(zhen)空滲(shen)(shen)(shen)碳的(de)溫(wen)(wen)(wen)度(du)一般高于普(pu)通(tong)氣(qi)(qi)(qi)體(ti)滲(shen)(shen)(shen)碳，常采(cai)(cai)用(yong)920～1040℃滲(shen)(shen)(shen)入(ru)(ru)和(he)(he)擴(kuo)散(san)可(ke)(ke)按所(suo)示(shi)分(fen)兩階段，也可(ke)(ke)用(yong)脈沖式(shi)通(tong)氣(qi)(qi)(qi)、停(ting)氣(qi)(qi)(qi)，多(duo)段式(shi)的(de)滲(shen)(shen)(shen)一擴(kuo)相(xiang)間(jian)，效果更好。由于溫(wen)(wen)(wen)度(du)高，尤(you)其表面(mian)潔凈、有活性(xing)，真(zhen)空滲(shen)(shen)(shen)碳層(ceng)形(xing)成速(su)度(du)比(bi)普(pu)通(tong)氣(qi)(qi)(qi)體(ti)、液體(ti)和(he)(he)固體(ti)滲(shen)(shen)(shen)碳快，如要(yao)求滲(shen)(shen)(shen)層(ceng)為(wei)1mm時，在(zai)927℃只需5h，而(er)1033℃僅需1h。

　　精密鋼管硬度(du)與變形(xing)

　　取兩(liang)塊(kuai)式樣(yang)，一塊(kuai)用(yong)于研究不同(tong)形變程度對硬(ying)度的影(ying)響，另一塊(kuai)研究不同(tong)溫度對性能的影(ying)響。

　　冷(leng)變(bian)(bian)(bian)形(xing)(xing)強(qiang)(qiang)化在(zai)實際生(sheng)產(chan)中具有(you)重要的(de)(de)(de)意義。首先(xian)這是一種(zhong)重要的(de)(de)(de)強(qiang)(qiang)化材料的(de)(de)(de)手段(duan)，尤其對用(yong)(yong)熱處理不能強(qiang)(qiang)化的(de)(de)(de)材料來說，顯得更(geng)為(wei)重要。其次，冷(leng)變(bian)(bian)(bian)形(xing)(xing)強(qiang)(qiang)化有(you)利于金屬的(de)(de)(de)變(bian)(bian)(bian)形(xing)(xing)均勻(yun)。因為(wei)精密(mi)(mi)鋼管的(de)(de)(de)變(bian)(bian)(bian)形(xing)(xing)部分產(chan)生(sheng)硬化，將使變(bian)(bian)(bian)形(xing)(xing)向未變(bian)(bian)(bian)形(xing)(xing)或變(bian)(bian)(bian)形(xing)(xing)較(jiao)少(shao)的(de)(de)(de)部分繼(ji)續發展。第三，冷(leng)變(bian)(bian)(bian)形(xing)(xing)強(qiang)(qiang)化可以(yi)提高(gao)構件在(zai)使用(yong)(yong)過(guo)程(cheng)中的(de)(de)(de)安全性，構件一旦超載(zai)，產(chan)生(sheng)塑性變(bian)(bian)(bian)形(xing)(xing)，由于強(qiang)(qiang)化作用(yong)(yong)，可防(fang)止(zhi)構件突(tu)然(ran)斷裂。但是，冷(leng)變(bian)(bian)(bian)形(xing)(xing)強(qiang)(qiang)化也(ye)給精密(mi)(mi)鋼管的(de)(de)(de)繼(ji)續變(bian)(bian)(bian)形(xing)(xing)帶來困難，甚至出現(xian)裂紋。因此(ci)，在(zai)精密(mi)(mi)鋼管變(bian)(bian)(bian)形(xing)(xing)和加工過(guo)程(cheng)中常進行"中間(jian)退火(huo)"，以(yi)消除它的(de)(de)(de)不利影(ying)響。