The influence of raw powder particle size on the properties and microstructures of Ti (C, N)-based cermets has been studied. The conclusions are as follows: The microstructures of cermets were composed of two kinds of...The influence of raw powder particle size on the properties and microstructures of Ti (C, N)-based cermets has been studied. The conclusions are as follows: The microstructures of cermets were composed of two kinds of grains, the one with black cores surrounded by obvious rim structures, and the other whose cores were white with unconspicuous rim structures and adhesive phase. In the cermet made from fine powders, the amount of grains with white cores was much more than that in cermet made from coarse powders. In addition, their properties were also much better.展开更多
Fe-based alloy coatings reinforced by Ti（ C, N） particles was produced through CO2 laser cladding technology. The microstructure of laser cladding coating was analyzed by means of X-ray diffraction （ XRD ）, transm...Fe-based alloy coatings reinforced by Ti（ C, N） particles was produced through CO2 laser cladding technology. The microstructure of laser cladding coating was analyzed by means of X-ray diffraction （ XRD ）, transmission electron microscopy （TEM） , selected area electron diffraction （ SAED ） , scanning electron microscopy （SEM） and electron probe microscopic analyzer （ EPMA ）. The mechanical property of the layer was measured by using microhardness meter. The results show that Ti （ C0. 3 N0. 7 ） panicles are introduced by an in-situ metallurgical reaction between TiN particle and graphite powder during laser cladding process. Titanium carbonitrides particles existed in the layer are fairly fine, ranging from 0. 1 μm to 5.0 μm, and evenly dispersed in the metal α-Fe matrix. Most of them take on nearly rhombus shape, and some of them are irregular in shape. The microhardness of laser cladding layer ranges from 770 HV0. 3 to 850 HV0. 3.展开更多
The precipitation of Ti(V)N(C)in high-carbon steel PD_3 during thermomechanicol treatment at austenitic temperatures after deformation has been observed.The average size of Ti(V)N(C)particles may reduce with the incre...The precipitation of Ti(V)N(C)in high-carbon steel PD_3 during thermomechanicol treatment at austenitic temperatures after deformation has been observed.The average size of Ti(V)N(C)particles may reduce with the increase of strain and the decrease of thermomechanical treatment temperature,and vise versa.The growth of Ti(V)N(C)particles at 920°C is found to be controlled by the interface reaction between precipitated particles and matrix.展开更多
Fe-based alloy layer reinforced by Ti（C,N） particles was produced on the surface of cast steel. X ray dif fraction （XRD） was used for phase identification in the composite coating. The microstructure of laser clad...Fe-based alloy layer reinforced by Ti（C,N） particles was produced on the surface of cast steel. X ray dif fraction （XRD） was used for phase identification in the composite coating. The microstructure of laser cladding layer was analyzed by means of optical microscope （OM）, electron probe microscope analyzer （EPMA）, scanning electron microscope （SEM） and transmission electron microscope （TEM）. The results show that Ti（C0.3 N0.7 ） particle is in-troduced by an in situ metallurgical reaction of TiN particle and graphite powder in the process of laser cladding. The shape of lots of Ti（C0.3 N0.7） particle is irregular. The sizes of Ti（C0. 3N0. 7） particles range from 0. 1 to 6.0 μm, and they are dispersed evenly in the matrix, which is fine dendritic or cellular crystal. A new kind of phase named Ti（C0.3 N0. 7 ） parti-cles are tightly bonded with α-Fe microstructure, and there is a clean and smooth phase interface between ceramic re-inforcement phase and the matrix.展开更多
基金the National Natural Science Foundation of China, the Doctoral EducationFoundation of China, the State Key Laboratory of Powde
文摘The influence of raw powder particle size on the properties and microstructures of Ti (C, N)-based cermets has been studied. The conclusions are as follows: The microstructures of cermets were composed of two kinds of grains, the one with black cores surrounded by obvious rim structures, and the other whose cores were white with unconspicuous rim structures and adhesive phase. In the cermet made from fine powders, the amount of grains with white cores was much more than that in cermet made from coarse powders. In addition, their properties were also much better.
文摘Fe-based alloy coatings reinforced by Ti（ C, N） particles was produced through CO2 laser cladding technology. The microstructure of laser cladding coating was analyzed by means of X-ray diffraction （ XRD ）, transmission electron microscopy （TEM） , selected area electron diffraction （ SAED ） , scanning electron microscopy （SEM） and electron probe microscopic analyzer （ EPMA ）. The mechanical property of the layer was measured by using microhardness meter. The results show that Ti （ C0. 3 N0. 7 ） panicles are introduced by an in-situ metallurgical reaction between TiN particle and graphite powder during laser cladding process. Titanium carbonitrides particles existed in the layer are fairly fine, ranging from 0. 1 μm to 5.0 μm, and evenly dispersed in the metal α-Fe matrix. Most of them take on nearly rhombus shape, and some of them are irregular in shape. The microhardness of laser cladding layer ranges from 770 HV0. 3 to 850 HV0. 3.
文摘The precipitation of Ti(V)N(C)in high-carbon steel PD_3 during thermomechanicol treatment at austenitic temperatures after deformation has been observed.The average size of Ti(V)N(C)particles may reduce with the increase of strain and the decrease of thermomechanical treatment temperature,and vise versa.The growth of Ti(V)N(C)particles at 920°C is found to be controlled by the interface reaction between precipitated particles and matrix.
基金Item Sponsored by Higher Education Fund of Inner Mongolia of China(nyzy11266)
文摘Fe-based alloy layer reinforced by Ti（C,N） particles was produced on the surface of cast steel. X ray dif fraction （XRD） was used for phase identification in the composite coating. The microstructure of laser cladding layer was analyzed by means of optical microscope （OM）, electron probe microscope analyzer （EPMA）, scanning electron microscope （SEM） and transmission electron microscope （TEM）. The results show that Ti（C0.3 N0.7 ） particle is in-troduced by an in situ metallurgical reaction of TiN particle and graphite powder in the process of laser cladding. The shape of lots of Ti（C0.3 N0.7） particle is irregular. The sizes of Ti（C0. 3N0. 7） particles range from 0. 1 to 6.0 μm, and they are dispersed evenly in the matrix, which is fine dendritic or cellular crystal. A new kind of phase named Ti（C0.3 N0. 7 ） parti-cles are tightly bonded with α-Fe microstructure, and there is a clean and smooth phase interface between ceramic re-inforcement phase and the matrix.
