Mouri T.,NTN Powder Metal Co. |
Sugai Y.,NTN Powder Metal Co. |
Ito Y.,NTN Powder Metal Co. |
Yuasa E.,Tokyo City University
Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy | Year: 2015
The composite journal bearings which have outer layer with high strength and inner layer with high wear resistance can be used as bearing materials in the industrial high-power machine. The complex layer bearing prepared by unification forming of two different mixed powders with Fe-Cu-C in outer layer and Fe-Cu-C-Ni-Mo in inner layer, and then it was sintered for various heating times at 1378 K∼1403 K. Mechanical properties of the bearing were investigated by determinations of Vickers hardness and radial crushing strength. The radial crushing strength of sintered bearing with outer layer composition of Fe-Cu-C mixed powder is increased by the addition of phosphorus of 0.2∼0.6 weight% (Specimen F). Nevertheless the apparent density of this complex bearing is low. The friction and wear properties in this bearing also were estimated. The sliding property to hardening steel shaft of the complex layer bearing was invested by swing-type sliding machine. Wear loss volume of Specimen F is low under high applied load it is very suitable for use of the industrial high-power machine.
Mouri T.,NTN Powder Metal Co.
Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A | Year: 2013
To develop the composite journal bearings (CJB) with high strength and high wear resistance, two different mixed powders were compacted in the shape of a double-layers cylinder. A mixed powder of Fe-Cu was used for an outer layer as back-up material. In inner layer, the mixed powder of Fe-Ni-Mo-Cu was used for wear resistance. The compacted cylindrical bearing was sintered at various temperatures. EPMA analysis was conducted to identify the distribution of elemental composition near the interface between the inner and outer layers. As a result, it was confirmed that the joining between the inner and outer layers in the CJB was achieved by a diffusion mechanism and the hardness increased with increasing the sintering temperature. After the sizing process, the CJB became higher circularity than journal bearing made by conventional P/M process. © 2013 The Japan Society of Mechanical Engineers.