材料期刊网

EFFECT OF LASER MELTING PROCESSING ON MICROSTRUCTURE OF GRAY CAST IRON

SHEN Lian LI Chenglao WANG Xiuling MA Lihua ZHU Daozhen Xi'an Jiaotong University , Xi'an , China Associate Professor , Dept.of Materials Science and Engineering , Xi'an Jiaotong University , Xi'an , China

金属学报(英文版)

The microstructure of the laser hardened layer on the HT20-40 gray cast iron after laser melting processing'was examined by optical microscopy,transmission electron microscopy (TEM)and scanning electron microscopy(SEM).Experimental results showed that a struc- ture with dendritic(M+A')and interdendriticly laminal transformed ledeburite (M+A'+Fe_3C)was produced after laser melting processing.The martensite is a mixture of dis- location martensite and twin martensite.Dislocation pile-ups and twins were found in the residual austenite.Microsegregation of composition and heterogeneity of microstructure were also apparent after laser melting processing.

关键词: laser processing , null , null