The recent developments in the photoinitiated cross-linking of polyethylene and the significant breakthrough of its industrial application are reviewed. The enhanced photo-initiation system, the dynamics of photoiniti...The recent developments in the photoinitiated cross-linking of polyethylene and the significant breakthrough of its industrial application are reviewed. The enhanced photo-initiation system, the dynamics of photoinitiated crosslinking, the optimum conditions, the crystal morphological structures and related properties, and the photo- and thermo-oxidation stability of photocrosslinked polyethylene (XLPE) materials have been elucidated systematically. A new technique for producing photocrosslinked XLPE-insulated wire and cable is described in detail. It can be expected that the future applications of photocrosslinking technique of polyolefins will be very promising.展开更多
The ultrasonic welding process for wires is being largely used on industry mainly on applications that involve the connectionbetween similar or different metals. The biggest benefit of this technology is the possibili...The ultrasonic welding process for wires is being largely used on industry mainly on applications that involve the connectionbetween similar or different metals. The biggest benefit of this technology is the possibility to perform the weld without additionmaterials, like terminals, metal rings or tapes. Manufacturing of wiring harnesses demands a significant amount of joining, such aswelding, crimping or soldering, to fulfill the desired layout of the harnesses and capacity requirements, but conventional connectionprocesses, face difficulties in joining multiple cross sections mainly due to the characteristics of the processes and equipment in use.Ultrasonic metal welding process overcomes these issues due to the solid-state characteristics inherent to the process itself that includethe excellent electrical properties of the joint. Several researches on ultrasonic metal welding are being done to define the fundamentalmechanisms behind this process and it is being seen that they are completely dependent on the cross section to be welded. With thisresearch we are trying to develop methods for process characterization and define acceptable quality parameters in this process. Themain topics addressed in this paper are the characterization the weld formation using copper-to-copper wires using optical microscopyand the analysis of insulation material when submitted to different thermal conditions.展开更多
A narrow channel setup was established and experiments were conducted to study the pre-ignition characteristics of wire insulation under overload conditions in weak buoyancy environment.The pre-ignition temperature va...A narrow channel setup was established and experiments were conducted to study the pre-ignition characteristics of wire insulation under overload conditions in weak buoyancy environment.The pre-ignition temperature variation trend of both the wire insulation and its nearby temperature monitoring points,the movement characteristics of smoke produced from the wire insulation and the ignition delay time of wire insulation were investigated.The results indicated that the narrow channel setup with a height of 10-15 mm was effective to suppress the effect of buoyancy,and the pre-ignition characteristics of wire insulation in microgravity could be predicted well by the narrow channel method.展开更多
基金The project was successively supported by the National Natural Science Foundation of China(No. 5880104, No. 59543002 and No. 59773030).
文摘The recent developments in the photoinitiated cross-linking of polyethylene and the significant breakthrough of its industrial application are reviewed. The enhanced photo-initiation system, the dynamics of photoinitiated crosslinking, the optimum conditions, the crystal morphological structures and related properties, and the photo- and thermo-oxidation stability of photocrosslinked polyethylene (XLPE) materials have been elucidated systematically. A new technique for producing photocrosslinked XLPE-insulated wire and cable is described in detail. It can be expected that the future applications of photocrosslinking technique of polyolefins will be very promising.
文摘The ultrasonic welding process for wires is being largely used on industry mainly on applications that involve the connectionbetween similar or different metals. The biggest benefit of this technology is the possibility to perform the weld without additionmaterials, like terminals, metal rings or tapes. Manufacturing of wiring harnesses demands a significant amount of joining, such aswelding, crimping or soldering, to fulfill the desired layout of the harnesses and capacity requirements, but conventional connectionprocesses, face difficulties in joining multiple cross sections mainly due to the characteristics of the processes and equipment in use.Ultrasonic metal welding process overcomes these issues due to the solid-state characteristics inherent to the process itself that includethe excellent electrical properties of the joint. Several researches on ultrasonic metal welding are being done to define the fundamentalmechanisms behind this process and it is being seen that they are completely dependent on the cross section to be welded. With thisresearch we are trying to develop methods for process characterization and define acceptable quality parameters in this process. Themain topics addressed in this paper are the characterization the weld formation using copper-to-copper wires using optical microscopyand the analysis of insulation material when submitted to different thermal conditions.
基金supported by the National Natural Science Foundation of China (Grant No. 50976115)the Pilot Special Programs of Chinese Academy of Sciences (Grant Nos. XDA04020208 and XDA04073202)
文摘A narrow channel setup was established and experiments were conducted to study the pre-ignition characteristics of wire insulation under overload conditions in weak buoyancy environment.The pre-ignition temperature variation trend of both the wire insulation and its nearby temperature monitoring points,the movement characteristics of smoke produced from the wire insulation and the ignition delay time of wire insulation were investigated.The results indicated that the narrow channel setup with a height of 10-15 mm was effective to suppress the effect of buoyancy,and the pre-ignition characteristics of wire insulation in microgravity could be predicted well by the narrow channel method.
