The tungsten-inert-gas (TIG) arc welding experiments of cemented carbide YG30 and steel 45 were carried out using the Ni-Fe-C filling alloys. The eta phases and mechanical properties of welded joints were analyzed by ...The tungsten-inert-gas (TIG) arc welding experiments of cemented carbide YG30 and steel 45 were carried out using the Ni-Fe-C filling alloys. The eta phases and mechanical properties of welded joints were analyzed by means of scanning electronic microscope (SEM), transmission electronic microscope (TEM) coupled with selected diffraction, electronic probe microanalysis and bending strength methods. The experimental results show that the chemical composition of the filling alloys affects eta phase formation. When the carbon and nickel contents in filling alloys are 0.61 wt% and 55.29 wt%, respectively, no eta phases form. And the joint bending strength is the highest to 1.352 GPa. But if they are 0.01wt% and 55.38wt%, the eta phases are formed at the boundaries of the cemented carbide and the weld, and the thickness of eta phase layer is about 110 micrometers. And the joint bending strength is low. Usually, these eta phases are anomalously granular, and easy to accumulate at the boundaries between cemented carbides and the weld. They are multiple M_6C rich in tungsten and iron.展开更多
Ni-Fe-C filler metal based on WC-30Co/Ni-Fe-C/45 steel is developed using TIGwelding method. The weld joints are studied by means of optical microscope, SEM, EPMA, X-rays andmicro hardness test etc. The results show t...Ni-Fe-C filler metal based on WC-30Co/Ni-Fe-C/45 steel is developed using TIGwelding method. The weld joints are studied by means of optical microscope, SEM, EPMA, X-rays andmicro hardness test etc. The results show that the weld joints of WC-30Co and 45 steel can beobtained by TIG welding using Ni-Fe-C alloys as filler metals. The harmful eta phase formed in thejoints is M_6C, M_(12)C type carbides. The poor carbon content of the W-Co-C system resulted fromthe carbon diffusion and the high ingredient Fe are the two vital factors inducing to eta phaseformation. It could be restricted by the addition of carbon element into Ni-Fe alloys.展开更多
基金financial supports from plan program of Dalian(grants No.2001145)
文摘The tungsten-inert-gas (TIG) arc welding experiments of cemented carbide YG30 and steel 45 were carried out using the Ni-Fe-C filling alloys. The eta phases and mechanical properties of welded joints were analyzed by means of scanning electronic microscope (SEM), transmission electronic microscope (TEM) coupled with selected diffraction, electronic probe microanalysis and bending strength methods. The experimental results show that the chemical composition of the filling alloys affects eta phase formation. When the carbon and nickel contents in filling alloys are 0.61 wt% and 55.29 wt%, respectively, no eta phases form. And the joint bending strength is the highest to 1.352 GPa. But if they are 0.01wt% and 55.38wt%, the eta phases are formed at the boundaries of the cemented carbide and the weld, and the thickness of eta phase layer is about 110 micrometers. And the joint bending strength is low. Usually, these eta phases are anomalously granular, and easy to accumulate at the boundaries between cemented carbides and the weld. They are multiple M_6C rich in tungsten and iron.
文摘Ni-Fe-C filler metal based on WC-30Co/Ni-Fe-C/45 steel is developed using TIGwelding method. The weld joints are studied by means of optical microscope, SEM, EPMA, X-rays andmicro hardness test etc. The results show that the weld joints of WC-30Co and 45 steel can beobtained by TIG welding using Ni-Fe-C alloys as filler metals. The harmful eta phase formed in thejoints is M_6C, M_(12)C type carbides. The poor carbon content of the W-Co-C system resulted fromthe carbon diffusion and the high ingredient Fe are the two vital factors inducing to eta phaseformation. It could be restricted by the addition of carbon element into Ni-Fe alloys.
