For sure guys I won't just pop out parts and replace them just so, I will check datasheets and infos about compatibility of the device and pinout arrangement etc.
But thanks for the precaution.
Reading your writings I slightly realized something what is maybe a better solution for my project than this what I built up and posted in my first post.
Maybe it is a better solution to avoid an active clamping circuit and using the avalanche behaviour of a proper mosfet.
I think from reading on the net and datasheets, to use the avalanche characteristic of a mosfet is more safer for the mosfet than to use an active clamping circuit.
From my perspective a mosfet which is suitable for driving inductive loads with internal protection etc. is a better option to use by me,
cos it is more precise calculated and built up compared to my calculations and maybe perspective of view.
Team of engineers done a much better protection and clamping for the specific mosfet than I can do as an average guy who has lot of electronics and programming knowledge but still not an official electronic engineer - part designer.
So, a mosfet let's say like the VND7N04 has a clamping circuit, a thermal and short protection circuit and a really dummi feedback but in conjunction with my dummy Attiny85 I could use that feedback to trigger an alarm and shut down immediately the circuit.
That sound so to me a more safer circuit than I did with all my mess of opto, clamping diode etc...
What do you think about this thinking path?
Maybe you can advice me a better or newer mosfet for my purpose?
btw. in what software was done that nice simulation what was posted by Zero999 ?
Thank you all of you for your time and help.
I learned lot of things from you.
My best regards.