給大(da)家(jia)介紹下(xia)(xia)熱(re)(re)(re)處(chu)(chu)理(li)加(jia)熱(re)(re)(re)溫(wen)(wen)(wen)度(du)三種現(xian)象:1、一般過(guo)熱(re)(re)(re):熱(re)(re)(re)處(chu)(chu)理(li)加(jia)熱(re)(re)(re)溫(wen)(wen)(wen)度(du)過(guo)高(gao)(gao)或在高(gao)(gao)溫(wen)(wen)(wen)下(xia)(xia)保溫(wen)(wen)(wen)時(shi)(shi)間(jian)過(guo)長,引起奧氏(shi)(shi)(shi)體晶(jing)(jing)(jing)(jing)粒(li)(li)(li)粗(cu)(cu)化(hua)(hua)稱(cheng)為(wei)過(guo)熱(re)(re)(re)。粗(cu)(cu)大(da)的(de)(de)(de)奧氏(shi)(shi)(shi)體晶(jing)(jing)(jing)(jing)粒(li)(li)(li)會(hui)導致鋼(gang)(gang)的(de)(de)(de)強韌(ren)性(xing)(xing)降低(di),脆性(xing)(xing)轉變溫(wen)(wen)(wen)度(du)升(sheng)高(gao)(gao),增加(jia)淬火(huo)(huo)(huo)時(shi)(shi)的(de)(de)(de)變形開裂傾向。而(er)導致過(guo)熱(re)(re)(re)的(de)(de)(de)原因是爐(lu)溫(wen)(wen)(wen)儀表失控(kong)或混(hun)料(liao)(常(chang)為(wei)不懂工(gong)藝(yi)發(fa)生(sheng)(sheng)的(de)(de)(de))。過(guo)熱(re)(re)(re)組(zu)織(zhi)(zhi)(zhi)可(ke)經退(tui)火(huo)(huo)(huo)、正(zheng)火(huo)(huo)(huo)或多次高(gao)(gao)溫(wen)(wen)(wen)回(hui)火(huo)(huo)(huo)后,在正(zheng)常(chang)情況下(xia)(xia)重新奧氏(shi)(shi)(shi)化(hua)(hua)使晶(jing)(jing)(jing)(jing)粒(li)(li)(li)細化(hua)(hua)。 2、斷口(kou)遺傳(chuan):熱(re)(re)(re)處(chu)(chu)理(li)有過(guo)熱(re)(re)(re)組(zu)織(zhi)(zhi)(zhi)的(de)(de)(de)鋼(gang)(gang)材,重新加(jia)熱(re)(re)(re)淬火(huo)(huo)(huo)后,雖能使奧氏(shi)(shi)(shi)體晶(jing)(jing)(jing)(jing)粒(li)(li)(li)細化(hua)(hua),但有時(shi)(shi)仍出現(xian)粗(cu)(cu)大(da)顆粒(li)(li)(li)狀斷口(kou)。產(chan)生(sheng)(sheng)斷口(kou)遺傳(chuan)的(de)(de)(de)理(li)論爭議較多,一般認為(wei)曾因加(jia)熱(re)(re)(re)溫(wen)(wen)(wen)度(du)過(guo)高(gao)(gao)而(er)使MnS之類(lei)的(de)(de)(de)雜(za)物溶入奧氏(shi)(shi)(shi)體并富集于晶(jing)(jing)(jing)(jing)界(jie)(jie)面(mian),而(er)冷卻時(shi)(shi)這些夾雜(za)物又會(hui)沿晶(jing)(jing)(jing)(jing)界(jie)(jie)面(mian)析出,受沖擊時(shi)(shi)易沿粗(cu)(cu)大(da)奧氏(shi)(shi)(shi)體晶(jing)(jing)(jing)(jing)界(jie)(jie)斷裂。 3 粗(cu)(cu)大(da)組(zu)織(zhi)(zhi)(zhi)的(de)(de)(de)遺傳(chuan):有粗(cu)(cu)大(da)馬(ma)氏(shi)(shi)(shi)體、貝(bei)氏(shi)(shi)(shi)體、魏(wei)氏(shi)(shi)(shi)體組(zu)織(zhi)(zhi)(zhi)的(de)(de)(de)鋼(gang)(gang)件(jian)重新奧氏(shi)(shi)(shi)化(hua)(hua)時(shi)(shi),以慢速加(jia)熱(re)(re)(re)到常(chang)規(gui)的(de)(de)(de)淬火(huo)(huo)(huo)溫(wen)(wen)(wen)度(du),甚至再低(di)一些,其奧氏(shi)(shi)(shi)體晶(jing)(jing)(jing)(jing)粒(li)(li)(li)仍然(ran)是粗(cu)(cu)大(da)的(de)(de)(de),這種現(xian)象稱(cheng)為(wei)組(zu)織(zhi)(zhi)(zhi)遺傳(chuan)性(xing)(xing)。要消除粗(cu)(cu)大(da)組(zu)織(zhi)(zhi)(zhi)的(de)(de)(de)遺傳(chuan)性(xing)(xing),可(ke)采用中間(jian)退(tui)火(huo)(huo)(huo)或多次高(gao)(gao)溫(wen)(wen)(wen)回(hui)火(huo)(huo)(huo)處(chu)(chu)理(li)。
鎮江井式爐其設備的特點:(1)、氣體氮化爐處理溫度低,時間短,工件變形小。(2)、氣體氮化爐不受鋼種限制,碳鋼、低合金鋼、工模具鋼、不銹鋼、鑄鐵及鐵基粉未冶金材料均可進行軟氮化處理。氣體氮化爐工件經軟氮化后的表面硬度與氮化工藝及材料有關。(3)、專業井式爐能(neng)顯(xian)著地提高(gao)工件(jian)的疲(pi)勞強(qiang)度、耐磨(mo)性和(he)(he)耐腐蝕性。氣(qi)體(ti)氮(dan)(dan)化爐(lu)在(zai)干摩擦(ca)條件(jian)下還具有(you)(you)抗(kang)擦(ca)傷和(he)(he)抗(kang)咬合等性能(neng)。(4)、氣(qi)體(ti)氮(dan)(dan)化爐(lu)由于軟(ruan)氮(dan)(dan)化層不(bu)存在(zai)脆性相,故(gu)氮(dan)(dan)化層因而具有(you)(you)一定的韌性,不(bu)容(rong)易剝落(luo)。因此,目前氣(qi)體(ti)氮(dan)(dan)化爐(lu)生產(chan)中軟(ruan)氮(dan)(dan)化已廣泛應用于模具、量具、刀具(如:高(gao)速鋼刀具)等、曲軸、齒輪、氣(qi)缸套、機械(xie)結(jie)構件(jian)等耐磨(mo)工件(jian)的處理。
給大(da)家(jia)介(jie)紹下(xia)多用(yong)(yong)爐氮(dan)氣(qi)純度(du)要(yao)求(qiu):1.本箱(xiang)式(shi)可(ke)(ke)(ke)(ke)控氣(qi)氛(fen)多用(yong)(yong)爐生產(chan)線主(zhu)要(yao)用(yong)(yong)于(yu)工(gong)(gong)件(jian)在(zai)可(ke)(ke)(ke)(ke)控氣(qi)氛(fen)下(xia)的(de)(de)氣(qi)體滲碳(tan)(tan)(tan)、碳(tan)(tan)(tan)氮(dan)共(gong)滲、滲碳(tan)(tan)(tan)后(hou)再次加(jia)熱淬(cui)火(huo)(huo)(huo)以及(ji)(ji)在(zai)保護(hu)氣(qi)氛(fen)下(xia)的(de)(de)淬(cui)火(huo)(huo)(huo)、回火(huo)(huo)(huo)。該設(she)備(bei)的(de)(de)操作(zuo)必須安全(quan)(quan)可(ke)(ke)(ke)(ke)靠(kao),直(zhi)接簡捷,采用(yong)(yong)計算(suan)機(ji)全(quan)(quan)過(guo)程自動控制(zhi),工(gong)(gong)藝(yi)穩(wen)定性好,在(zai)停電或其它意(yi)外情況下(xia),能(neng)夠實現自動充氮(dan),并可(ke)(ke)(ke)(ke)通過(guo)手動操作(zuo)完成(cheng)后(hou)續工(gong)(gong)序(xu)(xu),以確(que)保安全(quan)(quan)操作(zuo)和(he)產(chan)品質量(liang)。2.帶保護(hu)氣(qi)氛(fen)的(de)(de)回火(huo)(huo)(huo)爐用(yong)(yong)于(yu)工(gong)(gong)件(jian)的(de)(de)回火(huo)(huo)(huo)及(ji)(ji)時(shi)效(xiao)退火(huo)(huo)(huo)(用(yong)(yong)于(yu)高低(di)溫不同(tong)溫度(du)段時(shi)加(jia)熱功(gong)率應可(ke)(ke)(ke)(ke)調,帶有保護(hu)氣(qi)氛(fen)功(gong)能(neng))。3.用(yong)(yong)于(yu)滲碳(tan)(tan)(tan)、碳(tan)(tan)(tan)氮(dan)共(gong)滲前(qian)及(ji)(ji)滲碳(tan)(tan)(tan)、碳(tan)(tan)(tan)氮(dan)共(gong)滲淬(cui)火(huo)(huo)(huo)后(hou)工(gong)(gong)件(jian)的(de)(de)清(qing)(qing)洗(xi)、烘(hong)干。工(gong)(gong)件(jian)清(qing)(qing)洗(xi)、烘(hong)干后(hou)的(de)(de)清(qing)(qing)潔度(du)達(da)到滲碳(tan)(tan)(tan)、碳(tan)(tan)(tan)氮(dan)共(gong)滲要(yao)求(qiu)的(de)(de)標(biao)準(zhun),且工(gong)(gong)件(jian)無腐蝕(shi)、對下(xia)道工(gong)(gong)序(xu)(xu)熱處理質量(liang)無影(ying)響。4.裝卸料(liao)車用(yong)(yong)于(yu)箱(xiang)式(shi)可(ke)(ke)(ke)(ke)控氣(qi)氛(fen)多用(yong)(yong)爐、回火(huo)(huo)(huo)爐、清(qing)(qing)洗(xi)機(ji)的(de)(de)裝卸料(liao)及(ji)(ji)生產(chan)線各工(gong)(gong)序(xu)(xu)之(zhi)間(jian)工(gong)(gong)件(jian)的(de)(de)傳送。能(neng)夠準(zhun)確(que)按(an)規(gui)定位(wei)置完成(cheng)上述設(she)備(bei)工(gong)(gong)作(zuo)室的(de)(de)裝卸料(liao)。該生產(chan)線的(de)(de)所(suo)有設(she)備(bei)必須是全(quan)(quan)新設(she)備(bei)(包括所(suo)有零部件(jian)、元(yuan)器件(jian)和(he)附(fu)件(jian))。由不低(di)于(yu)國家(jia)標(biao)準(zhun)的(de)(de)先進可(ke)(ke)(ke)(ke)靠(kao)的(de)(de)材料(liao)、生產(chan)工(gong)(gong)藝(yi)及(ji)(ji)規(gui)范制(zhi)造而(er)成(cheng);投(tou)標(biao)方(fang)投(tou)標(biao)的(de)(de)同(tong)類設(she)備(bei)應具有在(zai)國內煤礦機(ji)械行業或同(tong)類行業二年以上的(de)(de)使用(yong)(yong)經驗(yan)。
給大(da)家介紹(shao)下常用(yong)熱處理多用(yong)爐(lu)(lu)(lu)(lu)(lu)爐(lu)(lu)(lu)(lu)(lu)型的選(xuan)擇:1.對(dui)于(yu)不能成批(pi)(pi)(pi)定型生產(chan)(chan)(chan)的,工件(jian)(jian)(jian)(jian)大(da)小不相等(deng)的,種(zhong)類較多的,要求工藝(yi)上具(ju)有通用(yong)性(xing)、多用(yong)性(xing)的,可(ke)選(xuan)用(yong)箱(xiang)(xiang)式(shi)(shi)多用(yong)爐(lu)(lu)(lu)(lu)(lu)。2.加(jia)熱長軸類及長的絲桿,管(guan)(guan)子等(deng)工件(jian)(jian)(jian)(jian)時(shi),可(ke)選(xuan)用(yong)深(shen)井式(shi)(shi)電爐(lu)(lu)(lu)(lu)(lu)。3.小批(pi)(pi)(pi)量(liang)(liang)的滲(shen)碳(tan)零(ling)件(jian)(jian)(jian)(jian),可(ke)選(xuan)用(yong)井式(shi)(shi)氣體(ti)滲(shen)碳(tan)爐(lu)(lu)(lu)(lu)(lu)。4.對(dui)于(yu)大(da)批(pi)(pi)(pi)量(liang)(liang)的汽車、拖拉機齒(chi)輪(lun)等(deng)零(ling)件(jian)(jian)(jian)(jian)的生產(chan)(chan)(chan)可(ke)選(xuan)連(lian)續式(shi)(shi)滲(shen)碳(tan)生產(chan)(chan)(chan)線或箱(xiang)(xiang)式(shi)(shi)多用(yong)爐(lu)(lu)(lu)(lu)(lu)。5.對(dui)沖壓件(jian)(jian)(jian)(jian)板(ban)材坯(pi)(pi)料的加(jia)熱大(da)批(pi)(pi)(pi)量(liang)(liang)生產(chan)(chan)(chan)時(shi),最好選(xuan)用(yong)滾動爐(lu)(lu)(lu)(lu)(lu),輥底爐(lu)(lu)(lu)(lu)(lu)。6.對(dui)成批(pi)(pi)(pi)的定型零(ling)件(jian)(jian)(jian)(jian),生產(chan)(chan)(chan)上可(ke)選(xuan)用(yong)推桿式(shi)(shi)或傳送帶式(shi)(shi)電阻爐(lu)(lu)(lu)(lu)(lu)(推桿爐(lu)(lu)(lu)(lu)(lu)或鑄帶爐(lu)(lu)(lu)(lu)(lu))7.小型機械零(ling)件(jian)(jian)(jian)(jian)如(ru):螺(luo)釘,螺(luo)母等(deng)可(ke)選(xuan)用(yong)振底式(shi)(shi)爐(lu)(lu)(lu)(lu)(lu)或網帶式(shi)(shi)爐(lu)(lu)(lu)(lu)(lu)。8.鋼球及滾柱熱處理可(ke)選(xuan)用(yong)內(nei)螺(luo)旋的回轉管(guan)(guan)爐(lu)(lu)(lu)(lu)(lu)。9.有色(se)(se)金(jin)屬(shu)錠(ding)坯(pi)(pi)在大(da)批(pi)(pi)(pi)量(liang)(liang)生產(chan)(chan)(chan)時(shi)可(ke)用(yong)推桿式(shi)(shi)爐(lu)(lu)(lu)(lu)(lu),而(er)對(dui)有色(se)(se)金(jin)屬(shu)小零(ling)件(jian)(jian)(jian)(jian)及材料可(ke)用(yong)空(kong)氣循環加(jia)熱爐(lu)(lu)(lu)(lu)(lu)。