Mitsubishi Materials Corporation

Osami Noguchi

Saburo Wakita

Akira Mitsuhashi

Hiroshi Miyata

Tsutomu Oka

Yoshio Chiba

A coated valve face of an engine valve is formed of an Fe-based alloy having a composition consisting essentially of, by weight, 0.7 to 1.5% of C, 10 to 15% of Mn, 24 to 30% of Cr, 6.1 to 9.8% of Mo, 10 to 15% of Ni, 0.1 to 0.4% of N, 0.2 to 1.5% of Si, and optionally at least one of 0.1 to 5% of Nb, 0.1 to 5% of Ta and 0.15% of W as required (the total content of Nb, Ta and W being limited to 5% or less), and the balance substantially Fe and inevitable impurities, and having a two-phase structure formed of an austenitic phase and an eutectic carbide phase. In another embodiment, the composition contains between 0.05 to 1% Co. The Fe-based alloys are preferably applied to the valve face by plasma beam or laser beam coating of powdered such alloys onto the valve face.

Engine valve having improved high-temperature wear resistance

A hard faced apparatus for applying hard facing to valves including a welding torch for performing hard facing on a valve head of each of valve blanks to be hard faced, a valve blank holding member for holding the valve blank in an oblique position such that the valve head of the valve blank faces the welding torch, and for rotating the valve blank about its axis, and valve transfer apparatus for transferring the valve blank to the valve blank holding member. The valve blank holding member includes valve attaching/positioning apparatus for attaching the valve blank while positioning an axis of the valve blank to be substantially aligned with an axis rotation of the valve blank holding member. Preferably, the valve attaching/positioning apparatus includes a support member formed in its distal end with a V-shaped groove to support the valve blank in an oblique position, axial moving apparatus for moving the support member in the axial direction of the valve blank, and radial moving apparatus for moving the support member in the radial direction of the valve blank.

Growing community of inventors

Okegawa, Japan

Osami Noguchi