1. Room Temperature Strength
Ordinary carbon steel (e.g., A36)：Has an ultimate tensile strength (UTS) of ~400–550 MPa and a yield strength of ~250–345 MPa. Most Inconel grades (even annealed Inconel 600, with UTS ~655–758 MPa) are stronger than ordinary carbon steel.
High-strength low-alloy (HSLA) steel or quenched-and-tempered (Q&T) steel (e.g., A514, 4140)：These steels can have much higher strength. For example, Q&T 4140 steel has a UTS of ~1000–1200 MPa, which is comparable to or slightly higher than annealed Inconel 600 (UTS ~655–758 MPa) but lower than cold-worked Inconel 600 (UTS ~965–1172 MPa) or high-performance grades like Inconel 718 (annealed UTS ~1100 MPa, heat-treated UTS up to ~1400 MPa).
Ultra-high-strength steel (UHSS, e.g., maraging steel)：Some UHSS grades (e.g., 18Ni maraging steel) can reach a UTS of 1800–2400 MPa, which exceeds most Inconel grades at room temperature.
2. Elevated Temperature Strength (Key Advantage of Inconel)
Steel：Loses strength rapidly as temperature rises. For example, ordinary carbon steel's UTS drops to ~100 MPa at 600°C, and even high-temperature steel (e.g., 316 stainless steel) sees its UTS fall to ~200 MPa at 800°C.
Inconel：Maintains exceptional strength at elevated temperatures due to its nickel-chromium matrix and resistance to thermal softening. For instance:
Annealed Inconel 600 has a UTS of ~310 MPa at 650°C (far higher than 316 stainless steel's ~250 MPa at the same temperature).
Inconel 718 (a precipitation-hardened grade) retains a UTS of ~800 MPa at 650°C and ~500 MPa at 800°C-performance that no conventional steel can match.
3. Other Strength-Related Considerations
Corrosion Resistance：Inconel's superior resistance to oxidation, creep, and corrosion in harsh environments (e.g., acidic media, marine settings, high-temperature gases) means it maintains its structural integrity (a form of "practical strength") longer than most steels, even if their room-temperature tensile strength is similar.
Creep Strength：At high temperatures, Inconel resists "creep" (slow deformation under constant load) far better than steel. For example, Inconel 600 can operate at 800°C for thousands of hours without significant creep, while steel would deform or fail quickly.
