两种蠕墨铸铁显微组织与切削加工性能

Microstructure and Machinability of Two Types of Vermicular Graphite Iron

采用金相显微镜、力学性能测试、加工性能测试等手段,观测和测试了不同合金化处理与不同蠕化效果的两种蠕墨铸铁的显微组织、拉伸强度、布氏硬度、基体显微硬度以及切削抗力。分析了两种蠕墨铸铁的切削加工性能和力学性能与显微组织之间的关系。研究结果发现:在蠕墨铸铁的石墨含量相同的条件下,蠕化率低的蠕墨铸铁中珠光体组织多,抗拉强度和硬度较高;蠕化率高的蠕墨铸铁显微组织更趋于均匀,切削抗力小,切削加工性能好。

The microstructure,tensile strength,Brinell hardness,matrix microhardness and cutting resistance of two types of vermicular graphite iron with different alloying and different vermicularizing were observed and tested by using metallurgical microscope,mechanical properties testing,machinability evaluation testing etc.The relationships of microstructure to machinability and mechanical property of the two types of vermicular graphite iron were analyzed respectively. The results show that with the same graphite content,the vermicular graphite iron with lower creep rates has more pearlite content,higher tensile strength and hardness. The micro structures of the vermicular graphite iron with higher creep rates tend to be more uniform,small cutting force and good machinability.