Method of brazing articles of stainless steel

A method of brazing an article comprising stainless steel parts, the method, comprising:

• applying an iron-based brazing filler material to the parts to be brazed and assembling the parts together, the iron-based brazing filler material comprising at least 40 wt % Fe, 14-21 wt % Cr, 5-21 wt % Ni, 0-8 wt % Mn, 0-2 wt % C, 0-15 wt % Hf and, either 6-15 wt % Si and 0.2-1.5 wt % B, or 4-9 wt % Si and 4-9 wt % P
• preheating the assembled parts in a non-oxidizing atmosphere, a reducing atmosphere, vacuum or combinations thereof to at least 400° C. and leaving the parts at the temperature of at least 400° C. for at least 15 minutes, and then raising the temperature to at least 900° C. and leaving the parts at the temperature of at least 900° C. for at least one hour to equalize the temperature of the parts so that the temperature is equal through the parts and the brazing material, the assembled parts then being heated to a brazing temperature of at least 1100° C. for at least 30 minutes to braze the parts and so that the brazing material flows into joints, pores, cracks, gaps or crevices to be filled or sealed;
• and
• allowing the brazing material to set thereby to form in the brazed article brazed areas having an average hardness of less than 600 HV1.