發(fā)布時(shí)間：2018-05-05 18:11

  本文選題：貝氏體鋼軌 + 組織演變　； 參考：《北京交通大學(xué)》2016年碩士論文

【摘要】：本論文研究了Mn-Si-Cr系貝氏體鋼軌用鋼的組織演變規(guī)律及不同形態(tài)貝氏體對(duì)其強(qiáng)韌性和抗磨損性能的影響規(guī)律,并獲得了優(yōu)化的鋼軌用鋼熱處理方案。以此為基礎(chǔ),進(jìn)一步研究了實(shí)際貝氏體鋼軌鋼和珠光體鋼軌鋼的抗磨損和抗接觸疲勞性能。等溫貝氏體和連續(xù)冷卻組織演變規(guī)律結(jié)果表明：貝氏體鋼軌鋼具有良好的貝氏體淬透性,在較寬冷卻速度(0.05℃/s～8℃/s)范圍內(nèi)可得到貝氏體/馬氏體復(fù)相組織,當(dāng)冷卻速度處于0.25℃/s～8℃/s范圍內(nèi)時(shí)奧氏體向貝氏體和馬氏體轉(zhuǎn)變動(dòng)力學(xué)相差不大；為該貝氏體鋼軌鋼采用空冷冷卻方式的可能性提供了科學(xué)依據(jù)。回火對(duì)空冷貝氏體鋼軌的研究結(jié)果表明：該貝氏體鋼軌鋼具有較高的回火抗力,當(dāng)回火溫度為280℃時(shí)貝氏體鋼軌鋼的強(qiáng)韌性匹配較佳且經(jīng)280℃回火后殘余奧氏體的熱穩(wěn)定性和機(jī)械穩(wěn)定性較高；為貝氏體鋼軌鋼的回火工藝提供了科學(xué)依據(jù)。工業(yè)化生產(chǎn)貝氏體鋼軌在空冷條件下組織轉(zhuǎn)變過(guò)程較復(fù)雜；并工業(yè)化生產(chǎn)的貝氏體鋼軌具有良好的強(qiáng)韌性匹配、其抗磨損和抗接觸疲勞性能均較佳。根據(jù)貝氏體鋼軌鋼的貝氏體等溫轉(zhuǎn)變、連續(xù)冷卻轉(zhuǎn)變規(guī)律及貝氏體鋼軌空冷過(guò)程中組織轉(zhuǎn)變規(guī)律設(shè)計(jì)了三種不同熱處理工藝以得到含有不同形態(tài)貝氏體的貝氏體/馬氏體復(fù)相組織。結(jié)果表明：針狀貝氏體/馬氏體復(fù)相組織比粒狀貝氏體/馬氏體復(fù)相組織的強(qiáng)韌性高、抗磨損性能好。本論文較系統(tǒng)地研究了貝氏體鋼軌鋼的貝氏體等溫淬火和連續(xù)冷卻轉(zhuǎn)變組織規(guī)律和工業(yè)化空冷貝氏體鋼軌組織演變規(guī)律�；�于上述演變規(guī)律設(shè)計(jì)相應(yīng)熱處理工藝,得到不同形態(tài)的貝氏體/馬氏體復(fù)相組織,從而調(diào)控貝氏體鋼軌鋼的性能。
[Abstract]:In this paper, the microstructure evolution law of Mn-Si-Cr bainitic rail steel and the influence of different bainite forms on its strength, toughness and wear resistance were studied, and an optimized heat treatment scheme for rail steel was obtained. On this basis, the wear resistance and contact fatigue resistance of bainitic rail steel and pearlite rail steel are further studied. The evolution law of isothermal bainite and continuous cooling microstructure shows that bainitic rail steel has good hardenability of bainite, and the bainite / martensite multiphase structure can be obtained within a wide cooling rate of 0.05 鈩，

本文編號(hào)：1848762