摘要
对EH36钢分别进行淬火+空冷、淬火+回火、淬火+回火+亚温淬火+回火的不同热处理。采用金相显微镜、拉伸试验机、冲击试验机及扫描电镜(SEM)测试了试样组织及力学性能。结果表明:原始组织主要为粗大的粒状铁素体以及聚集分布在基体的晶粒之间的珠光体,力学性能最差,同时断口中出现较大的断裂平面,韧窝较少较浅,为脆性断裂的特征;淬火+回火+亚温淬火+回火处理后,钢的铁素体晶粒尺寸发生明显细化,出现由渗碳体与珠光体组成的回火屈氏体,并且珠光体均匀弥散分布在铁索体晶粒之间,组织发生明显改善,力学性能最好,断口中的断裂平面消失,出现大量小而深的断裂韧窝。
The quenching ＋air cooling, quenching ＋ tempering, and quenching ＋tempering ＋subcritical quenching ＋ tempering treatments for EH36 steel were carried out respectively. The microstructure and mechanical properties of samples were tested by the microscope, tensile testing machine, impact testing machine and scanning electron microscopy （SEM）. The results show that the original microstructure is composed of many coarse granular ferrite and aggregated pearlite between grains in the matrix. The mechanical properties are the worst. Meanwhile, the larger fracture plane appears in the fracture, and toughening dimples are less and shallow, which is characteristic of brittle fracture. After the quenching＋ tempering＋subcritical quenching＋tempering treatment, the size of ferrite grain in the steel is obviously refined, and tempered troostite （the cementite and pearlite） appears. And pearlite is uniformly dispersed between ferrite grains. The microstructure improves obviously. The mechanical properties are the best. The fracture planes disappear in the fracture and large number of small and deep fracture toughness dimples appear.
出处
《热加工工艺》
CSCD
北大核心
2016年第12期152-155,共4页
Hot Working Technology
关键词
EH36
钢
亚温淬火
组织
力学性能
EH36 steel
subcritical quenching
microstructure
mechanical properties
