I believe it is important that the rates of heating and cooling should be
similar. However, if you are simulating a service profile, then follow
that cycle.

During mechanical cycling, assymetry in strain rates may have  a
substanial affect on life.

In simple terms, this is because the potential for damage from
time-dependent processes during slow straining is much greater that in
more rapid straining.

Of course there is a cut off when 'shock' intervenes at very high rates.

Bill Plumbridge

Solder Research Group

The Open University

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