發(fā)布時(shí)間：2018-10-13 16:57

【摘要】：以超高錳Fe-24Mn-1.0C(無鋁)和Fe-24Mn-7.1Al-1.0C(含鋁)鑄鋼為研究對(duì)象,采用水韌處理、水韌處理+時(shí)效處理的熱處理方法,研究鋁對(duì)不同熱處理?xiàng)l件下無鋁和含7.1%Al鑄鋼組織和性能的影響。利用光學(xué)顯微鏡和掃描電鏡觀察顯微組織,利用能譜分析和透射電鏡測(cè)試觀察析出物的成分、形貌;性能檢測(cè)包括抗拉強(qiáng)度、屈服強(qiáng)度、沖擊韌性(V型缺口)、斷后延伸率、初始硬度。結(jié)果表明,鋁的添加提高了鑄鋼Fe-24Mn-1.0C的層錯(cuò)能(γSFE),但卻降低了其抗拉強(qiáng)度、沖擊韌性和加工硬化速率。在時(shí)效過程中,鑄鋼Fe-24Mn-1.0C晶界處析出大量針狀粗大的碳化物,惡化了其性能(500℃時(shí)效2h)。而鋁元素增加了奧氏體基體中碳的穩(wěn)定性,抑制了粗大針狀碳化物的析出,析出納米級(jí)的(Fe,Mn)3AlC的κ-碳化物,明顯提高了基體的硬度和強(qiáng)度。鑄鋼Fe-24Mn-7.1Al-1.0C經(jīng)550℃時(shí)效2h后綜合力學(xué)性能達(dá)到最佳值,與常規(guī)水韌處理相比屈服強(qiáng)度提高到574MPa(提高40.0%,)抗拉強(qiáng)度為825 MPa,硬度提高到271HB(提高32.2%),斷后延伸率為32.0%,沖擊韌性為156J/cm2。
[Abstract]:The effects of aluminum on the microstructure and properties of Al-free and 7.1%Al cast steel under different heat treatment conditions were studied by using the heat treatment method of water toughening and water toughening aging, taking ultra-high manganese Fe-24Mn-1.0C and Fe-24Mn-7.1Al-1.0C cast steel as research objects. The microstructure was observed by optical microscope and scanning electron microscope, the composition and morphology of the precipitates were observed by energy dispersive analysis and transmission electron microscopy, and the tensile strength, yield strength, impact toughness (V-shaped notch), elongation after break were examined. Initial hardness. The results show that the addition of aluminum increases the stacking fault energy (緯 SFE),) of cast steel Fe-24Mn-1.0C, but decreases its tensile strength, impact toughness and work hardening rate. During the aging process, a large number of coarse needle-like carbides were precipitated at the grain boundary of cast steel Fe-24Mn-1.0C, which deteriorated the properties of the cast steel (aged at 500 鈩，

本文編號(hào)：2269314