Orifice plate and manufacturing method of the orifice plate

摘要

An orifice plate for liquid injection made of plate-shaped stainless steel, wherein an orifice is formed by shearing, is characterized in that the average crystal grain size of the stainless steel is 3 μm or less. The thickness of the plate-shaped stainless steel is 1.2 mm or less, and preferably 0.1 mm or less. The aspect ratio of the orifices is 0.8 or lower. The orifices are formed orthogonal to the plate surface, or slanted by 50° or at smaller angles. The plate-shaped stainless steel has a composition containing C, Mn, and Si.

主权项

1. A method of manufacturing an orifice plate for fluid injection, comprising:
subjecting austenitic stainless steel containing Ni and Cr to cold rolling and reverse transformation heat treatment to have an average crystal grain size of 3 μm or less to make a plate-shaped stainless steel having a thickness of 1.2 mm or less; and forming an orifice on the plate-shaped stainless steel by performing shear punching with a punch and a die, wherein the reverse transformation heat treatment is conducted so that the amount of stress-induced martensite generated by the cold rolling decreases to 5% or lower when measured using a ferrite content measuring instrument.