Fresh silver steel should be quite workable without annealing, with a quality, sharp, drill.  It’s possible your attempts to soften it have had the reverse effect though I would have thought that unlikely unless you had liquid quenched it.

Possibly a misunderstanding of the process?

1. Silver Steel from the supplier is soft, and can be turned, drilled, filed and milled without much bother.  Most of the cutting is done in the soft state.
2. For many purposes, it’s useful to harden the Silver Steel to resist wear.   Silver Steel makes this fairly easy.   The part is heated Cherry Red (750°C) throughout (big lumps take longer to heat through than little ones), then rapidly cooled by plunging into a liquid, normally cold water.
3. As the quench can make the metal over-hard, leaving it brittle, it’s common to Temper the metal by cooking it in a kitchen oven at about 150°C for 30 minutes.   Then remove and allow to cool naturally.   Tempering relaxes the crystal structure of the metal, making it much tougher, less hard and less brittle.

If a part has to be worked on after hardening, then grind rather than cut it.   Otherwise, the whole part has to be Annealed heated about 20°C above the alloy’s critical temperature and soak it at that temperature for about 1 hour per cubic inch of metal.    I don’t know what the critical temperature of Silver Steel is, something like 850°C I guess.   I quick look on the web was discouraging in that none of the instructions for heat retreating Silver Steel cover Annealing it.  Almost as if it’s never done!

Recommended to use an oven for annealing because the temperature and timings are quite critical.   It can be done with a torch but…

Also, be aware heat-treating isn’t infinitely repeatable.   Each cycle is likely to damage the metal.  For example, quenching in brine from too hot is likely to result in a mass of microcracks, and the only way to fix them is to melt the metal down entirely.

Dave

As Diogenes says maybe it is stainless which is notorious for blunting tools.
It is also possible that if you are only heating the end of a longer rod perhaps the body is remaining cold and quenching the heated end as soon as you remove the heat.

Don’t leave the rest of the rod attached, it will draw the heat away and make it cool faster than it would otherwise.  As mentioned already, heat to red and cool *slowly*.  Buried in a large bucket of ashes or vermiculite (should be available from a garden center) is good.

On 31 May 2024 at 16:04 Engine Doctor ( Phil ) Said:

..The center drill drills into the bar about 2 to 3mm then goes blunt as if the steel has gone hard again .

Cheap Chinese centre drilsl will do that. Combination of mediocre quality high speed steel and poorly ground cutting lips.

You don’t need to use a centre drill to start a drilled hole anyway. Common modern practice is to use a stub drill instead. In this case, such a small diameter hole to be drilled, I use a much larger centre drill as a stub drill. You use just the very tip of the large centre drill to make a small divot in the job, say 2mm diameter by maybe half a mm deep. Just enough to guide the tip of you regular drill bit when you start to drill the actual hole into the silver steel. That is all you need in this instance. Then drill on through with whatever regular drill bit you need to use.

If you start with a fresh piece of silver steel as supplied that has not been heated up etc. you should have no trouble drilling it with the above method.

If you are playing around hardening or annealing silver steel, note too that “cherry” red refers to the very dark red that cherries were back in blacksmithing days and not the bright red of the cherries your girlfriend gets in her cocktails today.

And another way of slowly cooling red-hot steel to soften it is to bury it in a bucket of powdered lime while it is still glowing red.

But as has already been said, you would be better off starting with a fresh piece of silver steel and machine it in as-supplied condition.