MIM 316L Maximum Operating Temperature: Engineering Data

When designing MIM 316L parts for elevated-temperature applications — under-hood automotive, exhaust components, near-engine sensors — the operating temperature limit is a critical design parameter.

MIM 316L — maximum service temperature:

Condition	Continuous Service	Intermittent Service	Limiting Factor
MIM 316L (>97% density)	400°C	800°C	Carbide precipitation above 425°C (sensitization)
MIM 316L (95-97% density)	350°C	750°C	Reduced density accelerates oxidation at grain boundaries
Wrought 316L (for reference)	425°C	850°C	Higher density provides slightly better high-temp performance
MIM 316L + electropolished	400°C	800°C	Surface finish improvement removes oxidation initiation sites

Why the limit exists: Above 425°C, chromium carbides (Cr₂₃C₆) precipitate at grain boundaries, depleting the surrounding matrix of chromium. This "sensitization" reduces corrosion resistance. In MIM parts with residual porosity, the larger surface area accelerates this effect. For continuous service above 400°C:

• MIM 316L is not recommended. Switch to MIM 17-4PH (good to 370-400°C in H900 condition, limited by over-aging)
• For 500-650°C: MIM Inconel 718 or MIM 17-4PH in over-aged condition (H1100-H1150, trades strength for thermal stability)

Quick Q: What temperature can MIM 316L handle?

Continuous: up to 400°C. Intermittent: up to 800°C (brief exposure). For sustained service above 400°C, switch to MIM 17-4PH (to 370°C) or Inconel 718 (to 650°C). The residual porosity in MIM parts (2-4%) slightly reduces high-temperature capability compared to wrought material.