Process for forging titanium-based material, process for producing engine valve, and engine valve

Abstract

The invention provides a process for forging a titanium-based material comprises the steps of: preparing a titanium-based sintered workpiece including at least one of ceramics particles and pores in a total amount of 1% or more by volume, the ceramics particles being thermodynamically stable in a titanium alloy; and heating the workpiece to a forging temperature and forging the same. In the production process, the pores or the ceramics particles inhibit the grain growth during forging. Accordingly, it is possible to carry out the forging at a relatively high temperature at which the titanium-based material exhibits a small resistance to deformation. Moreover, the titanium-based material can maintain an appropriate microstructure even after the forging. Consequently, the impact value and the fatigue strength are inhibited from decreasing.

Dependencies are inferred from the claim text.