Does an AC rated fuse blow at the same current DC
First of all, the voltage rating of the fuse is the maximum voltage at which the fuse is able to stop the current once it reaches the critical value (30 A, in your case).

If you have a current of the critical value at a higher voltage, there's a chance it will form an electric arc even if the fuse is broken, therefore the current will keep flowing anyway.

AC fuses are relatively easy to build, as the current is variable with time with a sinusoidal law. This means that the current goes to zero many times every second (for instance, 50 times every second if you're in most european countries), so you have a relatively low current most of the time. A continous current, at the same constant voltage (not alternated voltage) is therefore quite harder to stop.

In conclusion, if you have a 30 A fuse rated at 32 V AC, it won't probably behave like a 30 A fuse rated at 32 V DC.

It will interrupt the current flow if it reaches 30 A at, say, 24 V AC, but it probably won't if it reaches 30 A at, say, 24 V DC.