Review ER318 tensile strength, elongation, bend performance, and the factors that affect weld-metal test results.
ER318 combines stainless alloy content with useful tensile strength and ductility. Mechanical values must be interpreted according to the welding process, test condition, and applicable standard.
Typical ER318 Performance
| Property | Requirement | Typical value |
|---|---|---|
| Tensile strength | ≥550 MPa | 592 MPa |
| Elongation | ≥25% | 42% |
| Face bend | 180° | Pass |
| Root bend | 180° | Pass |
What Does Tensile Strength Show?
Tensile strength is the maximum stress reached during the test. It does not by itself establish suitability for fatigue, impact, creep, or corrosion service.
Why Is Elongation Important?
Elongation indicates ductility under the test conditions. Good elongation helps the weld accommodate deformation, but joint performance still depends on geometry, defects, residual stress, and service loading.
What Changes Mechanical Results?
- Welding process
- Heat input
- Shielding quality
- Base-metal dilution
- Specimen preparation
- Weld position
- Interpass temperature
- Post-weld heat treatment
- Testing standard
What Additional Tests May a Project Require?
Impact energy, ferrite content, hardness, corrosion testing, radiography, or procedure qualification may be required even when tensile and bend results are acceptable.
Dayang Welding recommends comparing ER318 data with the complete project specification rather than relying on one property.
