氮化锰铁在灰铸铁缸体中的应用

Application of Ferromanganese Nitride in Gray Iron Cylinder Block

试验研究了氮化锰铁对灰铸铁铸件基体组织、力学性能的影响,试验结果表明:(1)在一定范围内增加铸铁中的氮含量,片状石墨端部变圆钝,石墨片变粗、变短、变弯曲,基体中珠光体体积分数增加,灰铸铁的抗拉强度和硬度得到提高,但过量的氮含量容易导致铸件产生氮气孔缺陷,恶化铸件性能;(2)加入一定量的氮化锰铁,是生产高牌号灰铸铁铸件有效的工艺措施;(3)生产普通灰铸铁时,通过添加适量氮化锰铁,可减少Cu、Sn等合金元素的添加量,降低铸件的生产成本。

The effect of ferro manganese nitride on the matrix structure and mechanical properties of gray iron castings was experimentally studied.The test results showed that:(1)When the nitrogen content in cast iron was increased within a certain range,the ends of the flake graphite became rounded and blunt.The graphite sheets became thicker,shorter,and curved.The volume fraction of pearlite in the matrix increased,and the tensile strength and hardness were improved.But excessive nitrogen content could easily cause nitrogen pore defects in castings and worsen the performance of castings.(2)Adding a certain amount of ferromanganese nitride was an effective process measure for producing high-grade gray iron castings.(3)When producing ordinary gray iron,adding an appropriate amount of ferromanganese nitride could reduce the amount of Cu,Sn and other alloying elements requirement,and reduced the production cost of castings.