發(fā)布時間：2018-11-28 08:10

【摘要】：對一種Mo-Ti微合金鋼進(jìn)行了熱軋實驗,研究了不同工藝條件下的組織特征、析出行為及低溫沖擊性能。結(jié)果表明,隨著終軋溫度及終冷溫度的降低,實驗鋼的屈服強度和抗拉強度均有所升高;當(dāng)終軋溫度較高時,細(xì)小的析出物主要在冷卻及模擬卷取過程中產(chǎn)生,當(dāng)終軋溫度較低時,細(xì)小的析出物主要由應(yīng)變誘導(dǎo)析出及冷卻、模擬卷取過程的析出物組成;實驗鋼的組織以鐵素體為主,隨著終軋溫度及終冷溫度的降低,晶粒尺寸明顯細(xì)化,同時,組織中滲碳體及鈦的碳化物等島狀物的尺寸也變小,大角度晶界比例增加,低溫沖擊裂紋由脆性斷裂變?yōu)轫g性斷裂;當(dāng)終軋溫度為800~810℃,終冷溫度分別為615℃和500℃時,實驗鋼的屈服強度分別為738 MPa及768 MPa,抗拉強度分別為857 MPa和872 MPa,伸長率為18%~19%,其韌脆轉(zhuǎn)變溫度低于-70℃,實驗鋼具有良好的強度及韌性指標(biāo)。
[Abstract]:The hot rolling experiments of a Mo-Ti microalloyed steel were carried out. The microstructure, precipitation behavior and impact properties at low temperature were studied under different processing conditions. The results show that the yield strength and tensile strength of the experimental steel increase with the decrease of the final rolling temperature and the final cooling temperature. When the final rolling temperature is high, the fine precipitates are mainly produced in the process of cooling and simulated coiling, and when the final rolling temperature is low, the fine precipitates are mainly composed of strain-induced precipitation and cooling, and the precipitates in the simulated coiling process are composed of the precipitates. The microstructure of the experimental steel is mainly ferrite. With the decrease of the final rolling temperature and the final cooling temperature, the grain size is obviously refined. At the same time, the size of the cementite and titanium carbides in the microstructure also becomes smaller, and the ratio of large angle grain boundary increases. The low temperature impact crack changed from brittle fracture to ductile fracture. When the final rolling temperature is 800 鈩，

本文編號：2362308