The triggers are a carbon steel . But not super tempered.
But when I bend them , I do heat them up and bend them slowly.
But to do the bending, you have to have the trigger completely out of the trigger assembly or the heat will effect or soften other parts or springs of the trigger.
After I heat an anneal the trigger , I try to bend it when it is almost Red hot not Glowing Red.
After I reshape the trigger I reheat it to light Red and dip it in motor oil to reset the temper .
Don’t cool it in water or it will make it fragile.
Dip it in oil when hot will also reblue the shiney areas you ground or scratched.
I have had to straightened or reshaped triggers so they fit better to the shape of the trigger guard when I build a custom rifle .
But some factory shapes of the triggers were not what I liked in the first place either.
So I tuned them also so they fit the shape and clearance to the trigger guard that I wanted.
You can Cut or File the trigger to the shape you want without heating it up.
And then just cold blue the shinny metal that you see afterwards.