Air-hardened machine components

A machine, comprising:

• at least one component including at least one of a track shoe or a cutting edge, the at least one component including:
• a first surface and a second surface opposing the first surface;
• a first edge defining a first end of the at least one component, the first end extending from the first surface to the second surface;
• a second edge defining a second end of the at least one component, the second end opposing the first end, the second end extending from the first surface to the second surface;
• and
• a third edge that defines a punchout hole extending from the first surface to the second surface, wherein the at least one component comprises at least approximately 5% bainite crystal structure and a hardness in a range of 40 HRC to 55 HRC.

A track chain assembly, comprising:

• a plurality of track shoes;
• a plurality of links;
• and
• a plurality of bushings, wherein at least one of the plurality of track shoes, the plurality of links, and the plurality of bushings is formed by:
• hot-rolling steel, the steel having carbon in a range of approximately 0.2% and approximately 0.4% by weight, manganese in a range of approximately 0.1% and approximately 2% by weight, and silicon in a range of approximately 0.1% and approximately 2% by weight;
• air-cooling the at least one of the plurality of track shoes, the plurality of links, and the plurality of bushings for a period of time;
• and
• machining the at least one of the plurality of track shoes, the plurality of links, and the plurality of bushings, during the period of time and at a temperature in a range of approximately 300° C. and approximately 1100° C.