A method of joining two ferrous alloy component parts. The method includes hot metal casting a portion of a first ferrous alloy component part onto a first joining surface of a low carbon intermediate element; friction fitting a joining surface of a second ferrous alloy component part against a second joining surface of the low carbon intermediate element; and fusion welding with a concentrated energy source the intermediate element to the second ferrous alloy component part. The hot metal casting includes flowing a molten ferrous alloy onto the textured first joining surface, wherein the molten ally encompasses tabs extending from the first joining surface and filling apertures defined in the intermediate element. Then cooling the molten ferrous alloy such that a metallurgical and mechanical bond is formed between the portion of the first ferrous alloy component part and the first joining surface of the low carbon intermediate element.