Compacted graphite iron Wikipedia
Compacted graphite iron (CGI), also known as vermicular graphite iron (GJV, VG, JV or GGV from the German: "Gusseisen mit Vermiculargraphit") especially in nonEnglish speaking countries, is a metal which is gaining popularity in applications that require either greater strength, or lower weight than cast iron.. Schelleng obtained a patent for the production of compacted graphite .