| BROACHING
MATERIALS: |
| Material |
"Broachability" |
Tool Design |
| Commonly
used grades of regular and free-machining steels. |
Generally very good. Relatively heavy cuts usually possible. |
15º to 20º hook angle depending on hardness. 0.½º
to 3º backoff. Use chipbreakers. |
| Stainless Steels |
Harder grades tend to dull teeth rapidly, but is generally
feasible. Medium cuts should be used. |
10 to 20º hook angle 2-5º backoff. Use chipbreakers. |
| NON-FERROUS
METALS |
| Brass & Bronze |
Generally quite good. Medium to heavy cuts are best. |
0º to 10º hook angle depending on material. 0.½º
back off. Use chipbreakers. |
| Aluminum, Magnesium,
Etc. |
Very good. Quite heavy cuts generally give best results. |
15 to 20º hook angle 1 to 3º backoff. Standard tools
for steel can be used successfully, but special designs give
improved results. |
| NON-METALICS |
| |
Must be individually evaluated, but good results can often
be achieved. |
Best tool design will depend on characteristics of material. |
| Cast or Malleable
Iron |
Good-Medium to heavy cuts are best. Cast iron is broached
dry. |
Face angles should be about 6-8 degrees, and back off about
the same as for ordinary steel. |
