🔧 Monel 400 Hardness Overview
Monel 400 (UNS N04400 / W.Nr. 2.4360) is a solid-solution nickel-copper alloy known for its excellent corrosion resistance and mechanical strength. It is not hardenable by heat treatment, so its hardness is determined by cold working or the annealed condition.
📊 Monel 400 Hardness Values
| Condition | Hardness (HB) | Hardness (HRB) | Remarks |
|---|---|---|---|
| Annealed | 65 – 150 HB | ~50 – 80 HRB | Softest state; best for forming/welding |
| Cold Worked | Up to 250 HB (max) | Up to ~95 HRB | Increases strength and hardness |
| ASTM B164 Bar Spec | Typically ≤ 200 HB | Standard for cold-drawn bar products |
✅ Key Notes:
Hardness increases with cold working (e.g., drawing, rolling).
No phase transformation on heating-remains a single-phase alloy.
Used where moderate strength and excellent corrosion resistance are required, especially in marine and chemical processing environments.
