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(fa)貨快,報(bao)價低,全國(guo)可發(fa),我司專業生產(chan),歡迎咨(zi)詢~

　　20#精(jing)密鋼管熱處理工藝

　　精密鋼管前奏

　　真(zhen)空退(tui)火(huo)(huo)優質彈(dan)簧鋼、工具鋼、精密(mi)鋼管的絲材(cai)，不銹鋼制品(pin)及鈦(tai)合金(jin)材(cai)，作光(guang)亮退(tui)火(huo)(huo)均可采用真(zhen)空處理。退(tui)火(huo)(huo)溫(wen)度(du)愈(yu)(yu)低，則要求真(zhen)空度(du)愈(yu)(yu)高。為(wei)防(fang)止鉻的蒸發及加速熱傳(chuan)導，一般采用載氣加熱(保溫(wen))法，并注意(yi)對(dui)不銹鋼和(he)鈦(tai)合金(jin)不宜用氮而應(ying)采用氬氣。

　　精密鋼管過程

　　真(zhen)空(kong)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)真(zhen)空(kong)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)爐(lu)(lu)(lu)(lu)按冷卻(que)(que)方法(fa)分為油(you)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)和(he)(he)氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)兩類，按工(gong)(gong)(gong)位(wei)(wei)數分為單室(shi)(shi)(shi)(shi)式(shi)(shi)和(he)(he)雙室(shi)(shi)(shi)(shi)式(shi)(shi)，904山\畏嘲(chao)均屬周期(qi)式(shi)(shi)作(zuo)業爐(lu)(lu)(lu)(lu)。真(zhen)空(kong)油(you)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)爐(lu)(lu)(lu)(lu)都是(shi)雙室(shi)(shi)(shi)(shi)的(de)(de)(de)(de)(de)(de)(de)，后(hou)(hou)室(shi)(shi)(shi)(shi)置電加(jia)熱(re)元件(jian)(jian)，前(qian)(qian)室(shi)(shi)(shi)(shi)的(de)(de)(de)(de)(de)(de)(de)下方置油(you)槽(cao)。工(gong)(gong)(gong)件(jian)(jian)完成(cheng)加(jia)熱(re)、保溫(wen)后(hou)(hou)移(yi)入前(qian)(qian)室(shi)(shi)(shi)(shi)，關(guan)閉中(zhong)(zhong)門后(hou)(hou)向(xiang)前(qian)(qian)室(shi)(shi)(shi)(shi)充(chong)入惰(duo)性(xing)(xing)氣(qi)(qi)至大(da)約2.66%26times;lO ～1.01%26times;10 Pa(200～760mm汞柱)，入油(you)。油(you)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)易引起(qi)工(gong)(gong)(gong)件(jian)(jian)表(biao)面變(bian)質(zhi)。由于(yu)(yu)表(biao)面活性(xing)(xing)大(da)，在(zai)(zai)短暫的(de)(de)(de)(de)(de)(de)(de)高(gao)溫(wen)油(you)膜作(zuo)用(yong)下即可發生顯著薄(bo)層滲碳，此外，碳黑和(he)(he)油(you)在(zai)(zai)表(biao)面的(de)(de)(de)(de)(de)(de)(de)粘附(fu)對簡化熱(re)處(chu)理流(liu)(liu)程很不利。真(zhen)空(kong)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)技術(shu)的(de)(de)(de)(de)(de)(de)(de)發展(zhan)主要(yao)在(zai)(zai)于(yu)(yu)研制(zhi)性(xing)(xing)能(neng)優良、工(gong)(gong)(gong)位(wei)(wei)單一(yi)的(de)(de)(de)(de)(de)(de)(de)氣(qi)(qi)冷淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)爐(lu)(lu)(lu)(lu)。前(qian)(qian)述(shu)雙室(shi)(shi)(shi)(shi)式(shi)(shi)爐(lu)(lu)(lu)(lu)亦(yi)可用(yong)于(yu)(yu)氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)(在(zai)(zai)前(qian)(qian)室(shi)(shi)(shi)(shi)噴氣(qi)(qi)冷卻(que)(que))，但雙工(gong)(gong)(gong)位(wei)(wei)式(shi)(shi)的(de)(de)(de)(de)(de)(de)(de)操作(zuo)使大(da)批(pi)量(liang)(liang)裝爐(lu)(lu)(lu)(lu)的(de)(de)(de)(de)(de)(de)(de)生產發生困難，也(ye)(ye)易在(zai)(zai)高(gao)溫(wen)移(yi)動中(zhong)(zhong)引起(qi)工(gong)(gong)(gong)件(jian)(jian)變(bian)形(xing)或改變(bian)工(gong)(gong)(gong)件(jian)(jian)方位(wei)(wei)增(zeng)加(jia)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)變(bian)形(xing)。單一(yi)工(gong)(gong)(gong)位(wei)(wei)的(de)(de)(de)(de)(de)(de)(de)氣(qi)(qi)冷淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)爐(lu)(lu)(lu)(lu)是(shi)在(zai)(zai)加(jia)熱(re)保溫(wen)完成(cheng)后(hou)(hou)在(zai)(zai)加(jia)熱(re)室(shi)(shi)(shi)(shi)內噴氣(qi)(qi)冷卻(que)(que)。氣(qi)(qi)冷的(de)(de)(de)(de)(de)(de)(de)冷速不如油(you)冷快，也(ye)(ye)低于(yu)(yu)傳(chuan)統淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)法(fa)中(zhong)(zhong)的(de)(de)(de)(de)(de)(de)(de)熔(rong)鹽等溫(wen)、分級淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)。因而(er)，不斷提高(gao)噴冷室(shi)(shi)(shi)(shi)壓力(li)，增(zeng)大(da)流(liu)(liu)量(liang)(liang)，以(yi)及采用(yong)摩爾質(zhi)量(liang)(liang)比氮和(he)(he)氬小(xiao)的(de)(de)(de)(de)(de)(de)(de)惰(duo)性(xing)(xing)氣(qi)(qi)體氦和(he)(he)氫，是(shi)當今真(zhen)空(kong)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)火(huo)(huo)技術(shu)發展(zhan)的(de)(de)(de)(de)(de)(de)(de)主流(liu)(liu)。70年(nian)代后(hou)(hou)期(qi)將氮氣(qi)(qi)噴冷的(de)(de)(de)(de)(de)(de)(de)壓力(li)從(1～2)%26times;10Pa提高(gao)到(5～6)%26times;10Pa，使冷卻(que)(que)能(neng)力(li)接(jie)(jie)近(jin)于(yu)(yu)常壓下的(de)(de)(de)(de)(de)(de)(de)油(you)冷。80年(nian)代中(zhong)(zhong)期(qi)出現超高(gao)壓氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)，用(yong)(10～20)%26times;10Pa的(de)(de)(de)(de)(de)(de)(de)氦，冷卻(que)(que)能(neng)力(li)等于(yu)(yu)或略高(gao)于(yu)(yu)油(you)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)，已進入工(gong)(gong)(gong)業實(shi)用(yong)。90年(nian)代初(chu)采用(yong)40%26times;10Pa的(de)(de)(de)(de)(de)(de)(de)氫氣(qi)(qi)，接(jie)(jie)近(jin)水(shui)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)的(de)(de)(de)(de)(de)(de)(de)冷卻(que)(que)能(neng)力(li)，尚處(chu)于(yu)(yu)起(qi)步階段。工(gong)(gong)(gong)業發達國家(jia)已進展(zhan)到以(yi)高(gao)壓(5～6)%26times;10。Pa氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)為主體，而(er)中(zhong)(zhong)國產氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)一(yi)些金屬的(de)(de)(de)(de)(de)(de)(de)蒸(zheng)氣(qi)(qi)壓(理論值)與溫(wen)度的(de)(de)(de)(de)(de)(de)(de)關(guan)系則尚處(chu)于(yu)(yu)一(yi)般加(jia)壓氣(qi)(qi)淬(cui)(cui)(cui)(cui)(cui)(cui)(cui)(2%26times;10Pa)型階段。

　　結(jie)果(guo)真(zhen)(zhen)空滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)為真(zhen)(zhen)空滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)一淬火(huo)(huo)工(gong)藝(yi)曲線。在真(zhen)(zhen)空中加熱到(dao)滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)溫(wen)(wen)(wen)度(du)(du)并保(bao)溫(wen)(wen)(wen)使(shi)表面凈化、活化之(zhi)后，通(tong)入(ru)(ru)稀薄(bo)滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)富化氣(qi)(qi)(見控制氣(qi)(qi)氛(fen)熱處理)，在大約(yue)1330Pa(10T0rr)負壓下(xia)進(jin)行滲(shen)(shen)(shen)(shen)入(ru)(ru)，然后停(ting)氣(qi)(qi)(降(jiang)壓)進(jin)行擴散。滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)后的精密鋼管(guan)淬火(huo)(huo)采用(yong)(yong)一次(ci)淬火(huo)(huo)法，即先停(ting)電，通(tong)氮(dan)冷(leng)(leng)卻工(gong)件至臨界點A，、以下(xia)，使(shi)內部發生相變，再停(ting)氣(qi)(qi)、開泵，升溫(wen)(wen)(wen)到(dao)Ac1，～Accm之(zhi)間(jian)。淬冷(leng)(leng)方法可(ke)(ke)(ke)采用(yong)(yong)氣(qi)(qi)冷(leng)(leng)或油(you)冷(leng)(leng)。后者為奧氏體化后移(yi)入(ru)(ru)前(qian)室(shi)，充氮(dan)至常壓，入(ru)(ru)油(you)。真(zhen)(zhen)空滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)的溫(wen)(wen)(wen)度(du)(du)一般高于普通(tong)氣(qi)(qi)體滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)，常采用(yong)(yong)920～1040℃滲(shen)(shen)(shen)(shen)入(ru)(ru)和擴散可(ke)(ke)(ke)按(an)所示(shi)分兩(liang)階(jie)段(duan)，也可(ke)(ke)(ke)用(yong)(yong)脈沖式通(tong)氣(qi)(qi)、停(ting)氣(qi)(qi)，多段(duan)式的滲(shen)(shen)(shen)(shen)一擴相間(jian)，效果(guo)更好。由于溫(wen)(wen)(wen)度(du)(du)高，尤其表面潔凈、有(you)活性(xing)，真(zhen)(zhen)空滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)層形成速度(du)(du)比普通(tong)氣(qi)(qi)體、液體和固體滲(shen)(shen)(shen)(shen)碳(tan)(tan)(tan)快，如要求滲(shen)(shen)(shen)(shen)層為1mm時，在927℃只需5h，而1033℃僅需1h。

　　精密鋼(gang)管硬度與變形(xing)

　　取兩塊式樣(yang)，一塊用于研究不同(tong)形變程度對硬度的(de)影(ying)響，另(ling)一塊研究不同(tong)溫度對性能的(de)影(ying)響。

　　冷變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)強(qiang)(qiang)化(hua)(hua)在(zai)實際(ji)生產中具有重要(yao)(yao)的意義。首先這是一種(zhong)重要(yao)(yao)的強(qiang)(qiang)化(hua)(hua)材料的手(shou)段，尤(you)其對用熱(re)處理(li)不能(neng)強(qiang)(qiang)化(hua)(hua)的材料來說，顯得(de)更為重要(yao)(yao)。其次，冷變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)強(qiang)(qiang)化(hua)(hua)有利于金屬的變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)均勻。因為精密(mi)鋼管的變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)部(bu)分(fen)產生硬(ying)化(hua)(hua)，將使變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)向未變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)或變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)較(jiao)少的部(bu)分(fen)繼(ji)(ji)續(xu)(xu)發展。第三，冷變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)強(qiang)(qiang)化(hua)(hua)可以(yi)提高構(gou)(gou)件在(zai)使用過程(cheng)(cheng)中的安全性，構(gou)(gou)件一旦超載，產生塑(su)性變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)，由于強(qiang)(qiang)化(hua)(hua)作用，可防止構(gou)(gou)件突然斷裂。但是，冷變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)強(qiang)(qiang)化(hua)(hua)也給精密(mi)鋼管的繼(ji)(ji)續(xu)(xu)變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)帶來困難，甚(shen)至出現裂紋。因此，在(zai)精密(mi)鋼管變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)和加(jia)工過程(cheng)(cheng)中常進行"中間退火"，以(yi)消除它(ta)的不利影響。