What is considered frame damage? The image shown is of the uni-body frame construction. Everything you see in this image is considered the "frame" or more accurately the structure of a modern vehicle.
Structural Aluminum vs. Structural Steel
The difference in repairing steel versus aluminum in practice depends on the aforementioned items, with training being a major part. There are some similarities, but there are also some big differences.
In steel repair, we’re always trying to find ways of reducing or eliminating heat’s effect. Aluminum is different. The mechanical properties of aluminum can be similar to high-strength steels or even ultra high-strength steels. The repair abilities are polar opposites. Heat is necessary to repair aluminum. The problem is, how much? Knowing the limits and how to monitor those limits is critical.
The use of “memory” in steel makes for returning a part to original shape a common practice. Aluminum has no such memory and must be reformed. This provides a major difference in repair. Whether you’re dealing with aluminum sheet metal or structural, aluminum will take time to repair. The work hardening of aluminum makes the damage much stronger than the surrounding metal. Reforming takes heat and time and some patience. Practice is the issue. I find that many technicians are nervous on the heating of damage for repair.