CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. ...CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. It is found that the wetting angle reaches the minimum value 13.2° and the maximum spreading area 178 mm2 is achieved when the amount of Ce is 0.75 wt%. And Ce remarkably reduces the surface tension of liquid alloy, which improves the climbing height along the diamond and forms a massive support profile. And the results show that Ce can effectively improve the transverse rupture strength （TRS） due to high wettability. The wear characteristics of the diamonds brazed with Cu-based alloy containing 0.75 wt% Ce mainly consist of integrity, micro-fracture, fracture and rubdown, diamonds pull-out can not easily happen.展开更多
Wang Junxia—Super Runner Running like a deer on the track at full speed, Wang Junxia dashed to the finish line among the audience’s thunderous applause and cheers. She won t he 10,000-meter long distance event in 29...Wang Junxia—Super Runner Running like a deer on the track at full speed, Wang Junxia dashed to the finish line among the audience’s thunderous applause and cheers. She won t he 10,000-meter long distance event in 29:31.78 at the Seventh National Games in Beijing on September 8, 1993—a full 42 seconds faster than the 30:31.74 world record set by the Norwegian Ingrid Kristiansen in July 1986 and her展开更多
基金Project supported by National Natural Science Foundation of China(51575179,51205126)Natural Science Foundation of Hunan Province(2017JJ3073,12JJB006)
文摘CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. It is found that the wetting angle reaches the minimum value 13.2° and the maximum spreading area 178 mm2 is achieved when the amount of Ce is 0.75 wt%. And Ce remarkably reduces the surface tension of liquid alloy, which improves the climbing height along the diamond and forms a massive support profile. And the results show that Ce can effectively improve the transverse rupture strength （TRS） due to high wettability. The wear characteristics of the diamonds brazed with Cu-based alloy containing 0.75 wt% Ce mainly consist of integrity, micro-fracture, fracture and rubdown, diamonds pull-out can not easily happen.
文摘Wang Junxia—Super Runner Running like a deer on the track at full speed, Wang Junxia dashed to the finish line among the audience’s thunderous applause and cheers. She won t he 10,000-meter long distance event in 29:31.78 at the Seventh National Games in Beijing on September 8, 1993—a full 42 seconds faster than the 30:31.74 world record set by the Norwegian Ingrid Kristiansen in July 1986 and her
