Patent ID: 7977857

Claim:
A spark plug for an internal combustion engine, the spark plug comprising: an elongated center electrode having a center electrode tip at one end and a terminal proximate the other end; an insulator substantially surrounding the center electrode, the insulator having a substantially cylindrical body with at least a first insulator section and a second insulator section, the first and second insulator sections having first and second diameters respectively and being separated by an insulator shoulder; and a ground shield having an elongated base section substantially surrounding the first insulator section, a frustoconical flange protruding from a first end of the base section to engage the insulator shoulder, and a ground electrode extending from a second end of the base section to define a spark gap with respect to the center electrode tip, the base section and the ground electrode being formed as separate components and secured together to form the ground shield, wherein the ground electrode is formed from a first material and the base section is formed from a second material, the second material being different from the first material and wherein only the first material is suitable for maintaining the spark gap between the center electrode tip and ground electrode.