Patent ID: 6166479
Filing Date: 2000-12-26
Classification: H01T

Abstract:
A spark plug comprising:a center electrode;an insulator provided outside said center electrode;a metallic shell provided outside said insulator;a ground electrode disposed to oppose said center electrode; anda spark discharge portion fixed on at least one of said center electrode and said ground electrode for defining a spark discharge gap, said spark discharge portion being formed from an alloy containing Ir as a main component, Rh in an amount of 0.2 to 10 wt. %, and Pt in an amount of at least 0.1 wt. % and not greater than 10 wt. %,wherein the ratio (WPt/WRh) of the Pt content WPt (wt. %) to the Rh content WRh (wt. %) is within the range of 0.1-1.5.