1.Practical Forging Characteristics: Inconel 600 vs. Stainless Steel
Forging Loads
Inconel 600 requires 2–3 times higher forging forces than stainless steel for equivalent reductions.
This demands larger, more powerful presses and stronger tooling.
Number of Forging Passes
Stainless steel can often be forged to shape in relatively few passes.
Inconel 600 requires many more passes with intermediate reheats to avoid excessive work-hardening and cracking.
Heating Requirements
Stainless steel can be heated quickly and is less sensitive to temperature variations.
Inconel 600 requires:
Slow, uniform heating
Precise temperature control
Longer soak times to ensure the entire workpiece reaches the correct temperature
Improper heating leads to cracking or incomplete deformation.
Grain Size Control
Inconel 600 is more susceptible to grain growth if overheated.
Stainless steel is more tolerant of temperature fluctuations during forging.
Controlling grain size in Inconel 600 is critical for achieving good mechanical properties.
Surface Oxidation and Scale Formation
Inconel 600 forms a tougher, more tenacious oxide layer than stainless steel.
This oxide can cause:
Die wear
Surface defects
Reduced surface finish
More aggressive descaling (e.g., shot blasting, pickling) is required.
2. Forging Practice Recommendations for Inconel 600 (Relative to Stainless Steel)
Use Higher Press Capacities
Due to higher flow stress, hydraulic or mechanical presses with greater tonnage are needed.
Precise Temperature Control
Use calibrated furnaces and monitor temperature closely.
Avoid overheating above 1180°C.
Limit Deformation per Pass
Smaller reductions per pass are necessary to prevent work-hardening and cracking.
More intermediate reheats are required compared to stainless steel.
Ensure Uniform Heating
Longer soak times and better furnace uniformity are needed to prevent hot spots.
Use Advanced Tooling Materials
Tooling must withstand higher temperatures and loads.
Materials such as H13, modified H13, or powder metallurgy tool steels are preferred.
Careful Descale Between Passes
Remove oxide scale to prevent die damage and surface defects.
