# How to temper a non-ferrous metal

Can non-ferrous metals/alloys (copper, brass, bronze) be tempered (made harder) by temperature control alone, like ferrous metals? I understand it's simple to anneal copper, brass, etc., just by making them hot enough.

I'm Wondering if it's possible to temper non-ferrous metals without having to either work-harden it or media-blast it (essentially work hardening).

• Most non elemental metals can be heat treated, due to the construct of the phase diagram. – t.c Oct 11 '14 at 5:49
• Your use of the word "temper" is incorrect for metallurgy in English. Temper normally means to reheat and partially soften a steel that has been hardened by quenching. There are a few very unusual steels ( high speed) that may harden during tempering. For nonferrous metals you could be describing "age hardening". – blacksmith37 Dec 1 '18 at 19:46

Most non-ferrous alloys are heated in order to form a solution.

## Techniques:

Annealing:

Most non-ferrous alloys that are heat-treatable are also annealed to relieve the hardness of cold working. These may be slowly cooled to allow full precipitation of the constituents and produce a refined microstructure.

Different annealing techniques are subjected with non-ferrous alloys like recrystallization annealing, partial annealing, full annealing, and final annealing.

Quenching

Quenching is a process of cooling a metal at a rapid rate. This is most often done to produce a martensite transformation. In ferrous alloys, this will often produce a harder metal, while non-ferrous alloys will usually become softer than normal.

Reference: Wikipedia

• I know you have been doing a lot better (and I appreciate it!), but it's still best to blockquote (using the >  character) quotes that are pulled directly from the text. – jonsca Oct 12 '14 at 8:02
• @jonsca I think this answer looks better in this way because all the text is from 3 to 4 different paragraph from wikipedia. But yes from next answer i will use blockquote. Even if you think this answer should be in blockquote i can edit that. – Freddy Oct 12 '14 at 8:33
• Yeah, I can see that most of it is in your own words, but the "Quenching" section is not. I would do a lead in like "As far as quenching (rapid cooling) goes," (or something like that) and then blockquote the rest. Anything you use verbatim like that should be quoted, honestly. I'm not trying to pick on you here (it probably seems like it, but not my intention), but we need to give quotes within sources the proper credit, even if it is Wikipedia. – jonsca Oct 12 '14 at 8:39
• Thanks, but that does not seem to answer my question: is it possible to harden non-ferrous metals by temperature change alone – cannotcompute Oct 12 '14 at 23:34

You have a misconception that tempering is hardening. It is softening done after hardening to relieve stresses, improve ductility and toughness .

From this source

In nonferrous alloys, eutectoid transformations, which play such a prominent role in steels, are seldom encountered.

On the other hand, the principles associated with chemical homogenization of cast structures are applicable to many alloys in both classes. Examination of the heat treatment used for nonferrous alloys reveals that a wide variety of processes are employed. . Annealing after cold working is a very important heat treatment for nonferrous alloys.

Basically if the non-ferrous alloy has a eutectoid region in its phase diagram , tempering can be used after hardening. But non-ferrous usually are not hardened in this way. Age hardening, Precipitation hardening, Dispersion strengthening are commonly seen in non-ferrous alloys.