论文部分内容阅读
用膨胀法测定了贝氏体钢的连续冷却转变曲线,对转变产物进行了显微组织观察,研究了冷却速率对贝氏体组织形成的影响,并讨论了合金元素对试验钢性能的影响。研究表明,试验钢在冷却速率为2℃/s时已有较多的贝氏体组织发生转变;合金元素V抑制了铁素体和珠光体的转变;Cr提高了贝氏体开始转变的温度。结果表明,在很宽温度围内都可以得到以贝氏体为主的转变组织;V的加入扩大了贝氏体转变区,细化了铁素体晶粒;适量Cr的加入提高了试验钢的抗拉强度,并降低了屈强比。
The continuous cooling transformation curve of bainitic steel was determined by dilatancy method. The microstructure of the transformed product was observed. The effect of cooling rate on the microstructure of bainite was studied. The effect of alloying elements on the properties of the steel was also discussed. The results show that more bainite has been transformed in the test steel at the cooling rate of 2 ℃ / s; alloying element V inhibits the transformation of ferrite and pearlite; and Cr increases the temperature at which bainite begins to change . The results show that the bainite-based transformation structure can be obtained in a wide range of temperature. The addition of V expands the bainite transformation zone and refine the ferrite grains. The addition of appropriate amount of Cr improves the experimental steel Tensile strength, and reduced yield ratio.