Stepper Motors' Temperature

Hello everyone,
I want to ask you about the temperature of stepper motors. My machine X carve worked 1 hour. But, I touch the stepper motors Y axis, I feel high temperature. Is it normal situation??

Anything below 175F (continous) is considered safe for most steppers.
Even idling steppers can feel warm, because power is used to keep them stationary.

If the temps exceed 175F you run the risk of destroying the magnets inside the stepper as they will demagnetize when reaching 290F or above. Magnets are inside and always hotter than the stepper housing itself.

If they run too hot, reduce current limit or consider using a longer stepper motor. Stepper driver quality also play a part.

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On one of my prusa i3s there is a known problem where the stepper for the extruded can get very hot (this is on the mk3s model) when this stepper gets hot the heat is transmitted down the shaft to the hob gear, this heat softens the plastic before going into the heat break. That causes terrible jams. I bought some aluminum heat sinks that are the size of the steppers. I got the thermal pads instead of thermal paste. This essentially let me stick the heat sinks on like a sticker. I didn’t use the optional fan that came in the package, because I was worried about weight on the x-carriage. It dramatically dropped the temperature of that stepper, and I don’t get clocks any more. It’s a cheap solution if your steppers are running marginally hot.
Those are the stickers. Note the adhesive isn’t strong enough to survive the whipping around of a cnc. So I used a black nylon wire tie to hold it on (the adhesive really does, this just reinforces it)

I also saw these, which I thought were quite clever:

At 175. You shouldn’t be able to keep your hands on it. Mine get hot but I can always keep my hand comfortable on it for a few seconds.

Oh and the heatsinks I ordered:

Thank you for your reply. Does this order need a fan?? or you put it on the stepper motor directly??

I just stuck the heat sinks onto the stepper directly via the heat tape. The movement of the axes will move the air around the heatsink. Again this isn’t a cooler for a GPU, you’re just trying to take the edge off the heat of the motor. But if they are super hot, then I’d consider a 40mm fan.