Welded components for mechanical equipment Cast-iron, alloys of copper, nickel, titanium, zirconium

This article discusses the conditions for joining various families of alloys by welding, brazing or soldering:

• cast iron ;

• copper and copper alloys ;

• nickel and its alloys ;

• titanium, zirconium and their alloys.

The specific features of each of the families studied, in terms of both their shaping and their physical and chemical properties, give them precise applications in many industrial sectors of welded mechanical engineering.

After a presentation of the physico-chemical properties required to understand the metallurgical problems posed by the weldability or brazeability of the various families, the article presents, through a functional classification, the characteristics of the alloys likely to be supplied according to the normative documents in force, and also specifies their behavior during welding or brazing. It also discusses the choice of the most appropriate joining process for homogeneous connections, as well as for heterogeneous connections, with particular reference to the various steel grades. The article also looks at the justification and conditions for post-assembly treatments. Finally, as this is an article deliberately aimed at the design of mechanical structures, it discusses, in the case of cast irons, the basis for dimensioning welded or brazed joints.

At the end of the article, readers will find a glossary and table of acronyms and symbols.