Composite excavating tooth

Claim 1

A replaceable composite excavating tooth for excavating earth, comprising: a cast metal tooth body and an insert comprised of an integral body formed of a wear-resistant Cr-cast iron material having a higher hardness than said cast metal tooth body, said cast metal tooth body solidifying on said Cr-cast iron insert and having top and bottom surfaces tapered toward a tip end thereof and two side surfaces, and said Cr-cast iron insert is located at a central portion between said top and bottom surfaces of said case metal tooth body, said insert having clearances between portions of said insert which are completely filled by the solidified cast metal of said tooth body, and a width substantially the same as the width between said side surfaces of said cast metal tooth body, said insert extending from said tip end toward an attachment part of said tooth, and terminating at a predetermined useable limit of said composite excavating tooth, and said insert is rigidly and integrally bonded internally of said cast metal tooth body by a diffusion layer of materials from said cast metal tooth body and said insert between said insert and said cast metal tooth body which enhances adhesion between said insert and said cast metal tooth body and selectively imparts desired wear-resistant characteristics to said composite excavating tooth.