Kimihiko Ando

Hardfaced Valve and P/M Valve Seat System for CNG and LPG Fuel Engines

When adapted for use in automotive engines, CNG and LPG are considered environmentally friendly compared to gasoline or diesel fuel. However, when these gaseous fuels are used, wear of the valve seat insert and valve face increases if materials meant for use with gasoline are adopted. In comparison to a gasoline engine, the oxide membrane that is formed on the sliding surfaces of the valve face and valve seat insert is limited. As a consequence, adhesion occurs and increased wear of these components is the result. Based on analysis materials that are more compatible with these gaseous fuels were developed.

Development of High Strength Sintered Steel by High Pressure Warm Compaction Using Die Wall Lubrication

The high pressure compaction without internal lubricant and the high green density even with the pore free density were achieved by the newly developed die wall lubricant for warm compaction. This developed die wall lubricated warm compaction followed by high temperature sintering resulted in improved mechanical property and almost no dimensional change. In this paper, the effects of increasing the green density on the sintered density, the dimensional change and the mechanical property are mainly discussed.