The use of ultrasonic cleaners in the jewelry industry is ubiquitous. The solutions used have three principal components; a detergent, a de-greasing agent, and a surfactant (wetting agent). Since the first two components are generally well known, I won't waste time explaining them. The Surfactant/ wetting agent (basically the same type of stuff as Jet-Dri that one puts into the dishwashing machine) causes the cleaner to "break" or not cling to the surface of the item, usually in the form of water drops, . Thus the elimination of water spotting on glassware....
On the rare occasions when we needed a substitute for the commercially available ultrasonic cleaning solution, we found the all-purpose cleaner "Top Job" pretty effective. I suspect any cleaner containing these three components will work sufficiently well, as long as the de-greaser component is adequate for the grease present- jewelry usually isn't lathered in grease or oil; so the degreasing component isn't as proportionally high.
The heating of the solution is usually important to speed up the effectiveness of the cleaning process.
Depending on the strength of the transducers in the ultrasonic unit, there might be slight "etching" effect on some of the aluminum alloys when subjected to both heated solution and the caustic formulas. Caveat Emptor! So if you are cleaning alloy brake calipers or ungreased aluminum parts, you might want to do so with the heat turned off. Any thing greasy or oily, though, the heated solution is fabulous; especially cassettes, freewheel, and Chains!