The Challenges of Working With Aluminum

The Challenges of Working With Aluminum

Aluminum alloys also have lower hardness, higher ductility, and lower melting points as compared to steel alloys (932 degrees F to 1,112 degrees F for aluminum versus about 2,732 degrees F for steel). These differences can mean that metalworking tools and techniques used for steel-working are not always optimized for aluminum working.

One common issue when it comes to manually grinding aluminum workpieces is the tendency for aluminum chips to stick onto the grinding wheel itself. When the wheel loads (clogs) up with metal chips, it is unable to remove any more metal from the workpiece. Figure 1 shows a standard grinding wheel after only a few minutes of use on aluminum. Because this grinding wheel was designed for use on steel—not aluminum—loading occurred, and the wheel stopped grinding effectively.

One practice that delays the onset of metal loading is the application of wax onto the grinding wheel. By applying a slippery substance on the wheel’s surface, it temporarily makes it harder for the aluminum chips to stick. However, as the wheel is used, the wax wears away and needs to be reapplied. This option is not ideal, as wax application takes time away from grinding and creates additional contamination on the workpiece, which needs to be cleaned up when the grinding is done. If the wax is not thoroughly cleaned from the workpiece, it can lead to defects in the weld.