What is the difference between Hastelloy and ss316?
When selecting materials for harsh environments, choosing the right alloy is critical. Both Hastelloy and stainless steel are common choices in the industrial sector due to their excellent properties. Understanding the differences between them can help you make an informed choice to ensure durability, cost-effectiveness, and performance.
This article will explore the key characteristics of Hastelloy and stainless steel, compare their properties, and provide you with recommendations for use in specific applications.
What is stainless steel?
Stainless steel is an iron-based alloy containing chromium that provides corrosion resistance. Common stainless steel grades include 304, 316, and 430 stainless steel. Depending on its chemical composition, stainless steel has varying levels of performance and is ideal for applications such as construction, food processing, and medical equipment.
What is Hastelloy?
Hastelloy is a nickel-based alloy known for its excellent corrosion resistance and high-temperature stability. Common grades such as Hastelloy C-276 and Hastelloy C-22 are widely used in chemical processing, petrochemical, and marine industries. The unique combination of nickel, molybdenum, and chromium gives Hastelloy excellent resistance to pitting, stress corrosion cracking, and oxidizing atmospheres.
Hastelloy Steel vs Stainless Steel Chemical Composition:
| Element | Hastelloy C-276 (%) | Stainless Steel 316 (%) |
|---|---|---|
| Ni | 57.0 | 10.0 – 14.0 |
| Cr | 14.5 – 16.5 | 16.0 – 18.0 |
| Mo | 15.0 – 17.0 | 2.0 – 3.0 |
| Fe | 4.0 – 7.0 | Balance |
| W | 3.0 – 4.5 | – |
| C | ≤ 0.01 | ≤ 0.08 |
| Mn | ≤ 1.0 | ≤ 2.0 |
| Si | ≤ 0.08 | ≤ 1.0 |
| P | ≤ 0.04 | ≤ 0.045 |
| S | ≤ 0.03 | ≤ 0.03 |
Hastelloy vs Stainless Steel Mechanical Properties:
| Performance | Hastelloy C-276 | Stainless Steel 316 |
|---|---|---|
| Tensile Strength (MPa) | 690 – 785 | 515 – 620 |
| Yield Strength (MPa) | 283 – 355 | 205 |
| Elongation (%) | 40 – 55 | 40 – 50 |
| Hardness (HB) | 200 – 240 | 150 – 217 |
| Impact Toughness (J) | high | Medium |
