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FAQs
| Some of the most frequently asked questions relate to machining Ferro-Tic® or heat treating it to full hardness. If you can’t find your answer here, please e-mail us. We’ll respond as soon as possible and perhaps add it to this page. |
Machining Techniques
Ferro-Tic alloys move very little during heat treatment because of the stable carbides in their structure. For example, Ferro-Tic Grade C will grow approximately .0005 inch per linear inch. Grade CM will shrink approximately .001 inch per linear inch.
Since stock removal is more rapid on annealed material, where possible all machining and grinding should be done in this condition. Where very close tolerance must be maintained, sufficient grinding stock should be allowed for removal after hardening.
Slender parts, thin walled rings or parts subject to heavy stock removal can be heat treated with minimum distortion when the following steps are used: in the annealed state they should be machined to .010" - .015" over the heat treat size, stress relieved, then machined to the heat treat size and hardened.
- Cutting speed must be slow
- Tools must be sharp and dry. Remove all oil before use.
- Do not use cutting fluids
- Maintain a heavy chip load – minimum .003" per cutting edge
- Heavy depths of cut should be taken.
If shiny spots appear, make certain tools are dry and check insert for wear or chipped edge. If problem persists, reduce cutting speeds.
- What are some parameters for lathe turning?
- Tool Geometry: 0-5 degree negative back rake, 5 degree side rake, .030"
Tool Material: Tungsten Carbide (C-5 Class or better)
Tool Setting: Slightly below center
Depth of Cut: .050" to .100"
Feed: .003" to .012" per revolution
Cutting Speed: 35 sfm
Coolant: None
- What are some parameters for milling?
- Tool Material & Type: Solid or brazed insert cutters - Use High Speed Steel/Cobalt or Tungsten Carbide with a tool geometry of a general purpose type. For Indexable Insert Cutters: Use Tungsten Carbide (C-5 Class or better) Tool geometry should be a double negative rake with a large lead angle.
Depth of Cut: .010" to .050"
Feed: .003" to .012" per cutting edge per revolution
Cutting Speed: 35 sfm
Coolant: None
- Can you Tap Ferro-Tic?
- We recommend that you drill for a 50% thread, apply an anti-seize compound to the tap and blow chips away with an air blast. For through holes, tap through in a steady motion. Do not "back off" like conventional tapping of steel. For blind holes, "back off" to remove chips from hole before bottoming out. Also, keep the length of thread to a minimum by relieving or counterboring. A thread length of 1-1/2 times the diameter is sufficient.
- My saw blades don’t seem to hold up. Can you make a recommendation for sawing?
- Tool geometry should be a 3 to 10 pitch blade, raker set. Saw material can be a hard back carbon steel or high speed steel bi-metal. Remember the cutting speed should be slow (30 sfm maximum) with a medium to heavy feed pressure. Coolant: None
- What is the heat treat cycle?
The chart below defines the heat treat cycle by grade:
| For additional information or other grades, contact us. | ||||
| Ferro-Tic Grade CM | 1975F –1 hour | -94F – 1 hour | 975 –1 hour | 950F – 1 hour |
| Ferro-Tic Grade C | 1750F – 1 hour | 375F – 1 hour | ||
| Ferro-Tic Grade SK | 1875F – 1 hour | Cold work or 400F – 1 hour |
Hot work 800F – 1 + 1 hour |
|
| Ferro-Tic Gr. CS-40 | 1875F - 1 hour | 400F – 1 hour | ||