本文選題：沖擊韌性 + 貝氏體　； 參考：《材料熱處理學(xué)報(bào)》2015年02期

【摘要】：采用掃描電子顯微鏡、透射電子顯微鏡和沖擊性能測(cè)試等方法,研究了正火冷卻速度和回火溫度對(duì)45Cr MOV鋼的組織和沖擊韌性及其斷口形貌的影響規(guī)律。結(jié)果表明,由于組織中有先共析鐵素體的存在,以及貝氏體板條較寬,因而45Cr MOV鋼正火后的沖擊韌性值較低。隨正火冷卻速度的升高,貝氏體中M-A島由多邊形及近球狀逐漸變?yōu)槠瑺�、�?xì)長(zhǎng)狀及尖角狀,但沖擊值稍有增加;在600℃以下溫度進(jìn)行回火時(shí),沖擊韌性變化不大,當(dāng)回火溫度超過(guò)600℃,由于發(fā)生了再結(jié)晶,沖擊韌性明顯增加。沖擊斷口纖維區(qū)和剪切唇所占比例隨回火溫度的升高而逐漸增加,回火溫度低于650℃的沖擊斷口放射區(qū)的微觀形貌均呈現(xiàn)準(zhǔn)解理斷裂特征。
[Abstract]:The effects of normalizing cooling rate and tempering temperature on the microstructure, impact toughness and fracture morphology of 45Cr MOV steel were studied by means of scanning electron microscope, transmission electron microscope and impact test. The results show that due to the presence of proeutectoid ferrite in the microstructure and the wide bainite lath, the impact toughness of 45Cr MOV steel after normalizing is lower. With the increase of normalizing cooling rate, M-A island in bainite gradually changed from polygon and near globular to flake, slender and sharp, but the impact value increased slightly, and the impact toughness changed little when tempering temperature below 600 鈩，

本文編號(hào)：1913876