Hydroelectric power equipment consists of a hydro-turbine and a hydrogenerator whose weldments have the features of complicated construction and large bulk as well as some parts operating under water. With the increas...Hydroelectric power equipment consists of a hydro-turbine and a hydrogenerator whose weldments have the features of complicated construction and large bulk as well as some parts operating under water. With the increase of unit rating of the hydroelectric power equipment, the application field of high strength steel and dissimilar steel has been enlarged. What to be introduced in this paper is the development of the welding technology of large hydroelectric generating equipment in China since the 1970s, and the development orientation of its welding construction and procedure in the future.展开更多
The rules such as process parameters affecting joint properties and theevolution principle of weld's microstructure have been researched by adopting diffusion weldingprocess to connect SiC_w/6061Al composite. Expe...The rules such as process parameters affecting joint properties and theevolution principle of weld's microstructure have been researched by adopting diffusion weldingprocess to connect SiC_w/6061Al composite. Experimental results show that there exists a criticaltemperature region between solid and liquid phase line of SiC_w/6061Al composite, and the regionwill shrink with the increasing of welding pressure. When diffusion welding occurred under thecritical temperature region, welding joint exhibits bad property of bonding, and the matrix and thereinforcement can't bond effectively. When diffusion welding occurred in the critical temperatureregion, the strength of welding joint changes widely with the variation of welding temperature. Whenwelding temperature varies in 10 deg C, the strength of welding joint will change obviously. Onlywhen welding temperature is higher than the critical temperature region, stable joint properties canbe obtained. Simultaneously the matrix and the reinforcement has better interfacial bonded indiffusion welding interface, and no obvious interface reaction occurred, and thus diffusion weldingof SiC_w/6061 Al composite can be successfully realized.展开更多
文摘Hydroelectric power equipment consists of a hydro-turbine and a hydrogenerator whose weldments have the features of complicated construction and large bulk as well as some parts operating under water. With the increase of unit rating of the hydroelectric power equipment, the application field of high strength steel and dissimilar steel has been enlarged. What to be introduced in this paper is the development of the welding technology of large hydroelectric generating equipment in China since the 1970s, and the development orientation of its welding construction and procedure in the future.
文摘The rules such as process parameters affecting joint properties and theevolution principle of weld's microstructure have been researched by adopting diffusion weldingprocess to connect SiC_w/6061Al composite. Experimental results show that there exists a criticaltemperature region between solid and liquid phase line of SiC_w/6061Al composite, and the regionwill shrink with the increasing of welding pressure. When diffusion welding occurred under thecritical temperature region, welding joint exhibits bad property of bonding, and the matrix and thereinforcement can't bond effectively. When diffusion welding occurred in the critical temperatureregion, the strength of welding joint changes widely with the variation of welding temperature. Whenwelding temperature varies in 10 deg C, the strength of welding joint will change obviously. Onlywhen welding temperature is higher than the critical temperature region, stable joint properties canbe obtained. Simultaneously the matrix and the reinforcement has better interfacial bonded indiffusion welding interface, and no obvious interface reaction occurred, and thus diffusion weldingof SiC_w/6061 Al composite can be successfully realized.
