They are indeed owned presently by Bohler as of 2005, but the poster didn't ask the question of who owned Avesta... However, I stand corrected in that it has been taken over by BOHLER-UDDELHOLM since October of 2005... This is from their "History" link:
"2005
BÖHLER-UDDEHOLM sets new records for sales, earnings and order intake. The acquisition of Edelstahlwerke Buderus AG (Germany) is concluded in late June, setting a key milestone for the growth course of the Group. At the end of October, the takeover of Avesta Welding AB (Sweden) is finalized. BÖHLER-UDDEHOLM successfully completes a capital increase at the beginning of June.
2006
BÖHLER-UDDEHOLM closes its third consecutive record year. The integration of the Buderus Edelstahl companies and Avesta Welding AB is completed. The Group increases capital expenditure significantly, constructs a production facility for welding consumables in Suzhou (China) and acquires Helmold, a producer of special cutting rules in the USA."
http://www.bohler-uddeholm.com/english/26_ENG_HTML.phpInconel 625 is a ERNiCrMo-3 as opposed to a ERNiCrMo-13 filler... So if you can find a filler that's close to the chemical composition of the P16 then use it as well especially for "Dissimilar" welding as is your specific application... Also, Inconel 625 has a small amount of Cu (Copper)which may be detrimental to the weld grain boundaries upon solidification when welding the 654 SMO to the carbon steel which is the application the poster described.
What's important as well is this: when the weld is NOT to be subsequently annealed, an overalloyed filler metal should be used... Because of the high corrosion resistance of 654 SMO, the degree of overalloying required is unusually high and so in comparison to Inconel 625 filler, there's not enough Mo for overalloying which is why P16, or a chemical composition equivalent is recommended instead for use on 654 SMO. It's all explained quite plainly and quite clearly in these two .pdf's as well as in the Avesta Welding Manual as well.
http://www.futurealloys.com/654smo.pdfhttp://www.outokumpu.com/42534.epibrwHenry