4130 is very different to aluminum. Try running aluminum alloys with a decent DOC and feed without coolant and you are almost certain to load up and break the tool, especially if it is a four flute.
However, running a TiAlN coated cutter in 4130 should be done dry. The coating needs to get very hot to activate it's lubricating properties.
600fpm with TiAlN is not really crazy depending on the DOC, stepover and feed. With a 1/2" four flute you should be able to run at this speed with a DOC of .4", maybe more, a stepover of no more than 20% and feed of 0.005" per tooth.
The goal with TiAlN coated cutters is to get a fast moving hot chip that does not efficiently conduct heat to the part or the tool. But the tool must not be buried deeply in the cut, however with the small stepover you benefit from radial chip thinning so the feed per tooth can be cranked to get very rapid metal removal.
You should do a search on trochoidal milling and peel milling to find out how fast you can run with the correct combination of tool, DOC, stepover and feed.