摘要
The 2 mm-thick SiCp/LD2 composite plates were electron beam welded at different heat inputs. The microstructures of welds were investigated by OM, TEM, SEM, and XRD, and the properties of welds were measured with MTS-810 testing system. The results show that the quantity and size of acicular Al4C3 precipitates (interfacial reaction product) decrease with the heat input decreasing. When the heat input lowers to 30 J/mm, the formation of needle-like Al4C3 can be prevented. The distributions of SiC in the fusion zones are more uniform than that in as-received composite. TEM analysis reveals that there are Al4C3 crystals on the surface of every survived particle, the needle-like Al4C3 observed under the optical microscope consists of many tabular Al4C3 crystals which have different orientations. With the increase of heat input, the fracture mechanism changes from ductile one to brittle one, the quantity of fractured particles on the fracture face decreases and the strength and ductility of the weld decrease.
The 2 mm-thick SiCp/LD2 composite plates were electron beam welded at different heat inputs. The microstructures of welds were investigated by OM, TEM, SEM, and XRD, and the properties of welds were measured with MTS-810 testing system. The results show that the quantity and size of acicular Al4C3 precipitates （interfacial reaction product） decrease with the heat input decreasing. When the heat input lowers to 30 J/mm, the formation of needle-like Al4C3 can be prevented. The distributions of SiC in the fusion zones are more uniform than that in as-received composite. TEM analysis reveals that there are Al4C3 crystals on the surface of every survived particle, the needle-like Al4C3 observed under the optical microscope consists of many tabular Al4C3 crystals which have different orientations. With the increase of heat input, the fracture mechanism changes from ductile one to brittle one, the quantity of fractured particles on the fracture face decreases and the strength and ductility of the weld decrease.
出处
《中国有色金属学会会刊：英文版》
EI
CSCD
2006年第4期818-823,共6页
Transactions of Nonferrous Metals Society of China
基金
Project(2004BS05010) supported by Shandong Youth Doctoral Foundation, China
