2016 年 63 巻 7 号 p. 543-547
We aimed to develop a new powder metallurgy process to produce next generation common rail diesel nozzles with tiny and complexly shaped holes. High-speed centrifugal compaction and powder metallurgy were used. Three nozzle samples with holes of straight and tapered (8°, 16°, enlarged inwardly) were made. Three samples without external and inner defects were examined by spray test, which was performed with an ambient pressure of 1 and 4 MPa, an injection pressure of 150 MPa, and was studied by filming using a high-speed camera at 8000 fps. The measuring parameters were the penetration, spray angle, and spray cone angle from the spray aperture. As the taper angle increased, the penetration and spray cone angle increased.
