soldering nichrome wire
A crimp is usually used inside heaters for connecting nichrome wire to other metal parts or wires. Since it can get hot, you'd need a bare metal (not plastic coated) butt crimp.



Its a very reliable method if you use the right tool and a very poor method if you make-do with pliers and brute force.  With the right tool, the two metals in a crimped bond are actually cold-welded together, forming a gas-tight bond.  Other connection methods (including soldering without sufficient flux) may leave oxide layers or admit oxygen which can affect conduction and mechanical strength. 

The "right tool" is the ratchet crimp tool recommended by the manufacturer for the particular crimp and wire. Ratchet tools ensure that the correct pressure is applied before they release (unless you use the emergency release lever which is only meant in case of trapped fingers). As opposed to a pair of pliers, which may under or overcrimp the part, not shape the crimp correctly, slip off etc. Ratchet crimp tools can and should be calibrated.