Processing variables are confounded when different alloys enter a heat treatment facility. Cooling temperatures and time periods adjust accordingly to metallurgical variances. Likewise, a worked hardened metal part is subjected to ingrained stress. The plastic deformation stress is removed by heat treating the part and making it workable again. These examples apply to steel, but non-ferrous metal treatment work emulates this standard iron-heavy processing configuration, although there are differences between the two metal families.
Cold Worked Parallelism
Non-ferrous metals use the same cold work techniques as ferrous products. Copper is bent in the workshop, then aluminium and zinc are sheared. They’re drawn and compressed just like a similarly profiled steel workpiece. Naturally, the metals we just mentioned are more ductile than iron, plus they’re characterised by different transformative temperatures, so the heat treatment work envelope has to adapt to these processing changes, but that cold working layout is relatively indistinguishable from the ferrous-sourced setup. However, there are always exceptions to any rule, and such is the case here, for some non-ferrous metals are not cold workable. Certain copper alloys, for example, resist cold workshop tooling methods.
Non-Ferrous Metal Heat Treatment
Although it’s true that these metallurgical groups are amazingly versatile, that versatility factor can hamper the heat treatment process. Essentially, iron-free metals don’t react as predictably as steel when they’re hardened or otherwise mechanically altered. They do subscribe to the annealing process, though, so a strain-hardened component can be softened by heat-releasing the grain’s internal stresses. Otherwise, using aluminium as an example here, a ferrous-centric hardening and quenching cycle is simply not an option. Instead, we call upon the services of a precipitation hardening process. It’s here that lower furnace temperatures age the alloys until precipitates are formed. Quenching does follow the hardening work, just like it does in a ferrous-oriented workshop, but this is a water quenching station, not an oil bath.
As proven by these changed processing variables, a non-ferrous metal heat treatment setup deploys its equipment in a different manner. There are temperature and time variables to account for, such as magnesium’s 300-320°C annealing temperature, then there’s the kinetics, the operability changes to incorporate into the process. Non-ferrous hardening technology takes a sharp turn into a contrasting methodology, a place where precipitation hardening and water quenching take charge. On top of this realisation, many grades and alloy forms sub-branch from the non-ferrous metal groups, and these groups require cold work (cold rolling) technology to accommodate their unique hardening requirements.