Aluminum Head softness testing

I was curious to ask the question of how do you test how soft the aluminum of a head may be? I have a few rebuilt aluminum heads that have been built by several people. I don’t know any of the history of them or how they taken care of. So I am not sure if the head has every been heated up to much and softened the aluminum or if its been retreated. They have all been resurfaced prior to watching any videos which made this question arise. I do not feel like wasting money on these heads if they are going to be costly to properly repair them.

Normal test is to measure how far a hardened point will go into the surfuce with a specific force, different materials use different forms of these tests and a common version is the Brinell*. Any metal treatment and many engineering shops should be able to do the test for you.

*There are several different tests, have a quick google for that and metalurgy (sp?), heat treatment, metal testing, etc, shops in your area.

Thank you very much Gord. I checked google but wasn’t sure what to believe what true and what was “fake news” so I went here. Will check my local area forsure now that I know what to specifically search and ask about.

Most engine machine shops will have a hardness tester and will be able to offer this service for you. Most will incorporate a hardness test prior to performing any work on a head.