Donald Gillies wrote:
What is melt-forging and is it still used?
The "Mighty" series of cranks were cold forged. "Melt Forging" is actually a marketing name for high pressure casting. The alloy is forced into the mold under high pressure (over 10,000 psi) and then cooled quickly with a water jacket around the mold. The Hierarchy for crank manufacturing is: Cold Forged, Hot Forged, Gravity Cast, Melt Forged.
What separates all these process is the amount of money needed for tooling & the time needed to complete a part. Cold forging requires the highest number of dies, Hot forging uses fewer and Gravity casting & melt forging only one mold but melt forging is quicker.
Hope that helps.