To provide a method for producing sliding parts capable of realizing the increase of the dimensional precision of a molded part, the increase of its hardness and the reduction of the porosity therein by the metal injection molding of a raw material equivalent to SUS440C and to obtain a swirling flow generating body of an injection valve produced by the producing method.
A compound for molding obtd. by mixing raw material powder as the material equivalent to SUS440C, graphite carbon by a amt. corresponding to the content of oxygen in this raw material and a binder is used and subjected to injection molding (injection molding stage 100). Next, the obtd. molded body is heated in a neutral atmosphere to remove almost the total content of the binder in the molded body (degreasing stage 101). Then, the degreased molded body is heated from a room temp. to 1000°C in a vacuum of ≤0.1333 Pa to reduce the content of oxygen in the molded body to ≤0.02% by the reaction of C+O → CO, and thereafter, its temp. is raised to 1250°C in an argon atmosphere of 133.3 to 3999 Pa, which is held for 2 hr, and the molded body is baked (baking stage 102).
AOTA MASAYUKI
MUNEZANE TAKESHI
SUMITA MAMORU
KASAI TAKAO
KAMIYAMA TAKURO
CITIZEN WATCH CO LTD
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