ASTM A194 GRADE 8MNA NUTS
ASTM A194 Grade 8MNA Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Nitrogen-Strengthened, Molybdenum-Bearing Austenitic Stainless Steel Fasteners (ASTM A194 Grade 8MNA / AISI 316N Class 1A). Review verified chemical matrices, high load thresholds, and post-machining solution annealing logs optimized for severe marine and high-pressure chemical systems.
What's Inside This A194 Grade 8MNA MTC Certificate
This sample mill test certificate mirrors the strict QA verification package standard for Class 1A post-machining solution-annealed, nitrogen-strengthened molybdenum stainless steel heavy hex nuts shipped from our facility for elite load-bearing systems globally.
- Full Traceability: Issued under tracking code TC No.: S49/26-XX, fully mapping back to verified melting lots to maintain continuous product verification.
- Class 1A Solution Annealing: Explicit verification that components have undergone mandatory solution heat treatment after the final machining, tapping, and forming phases, thoroughly reversing cold-work strains and ensuring maximum microstructural stability.
- Nitrogen Interstitial Strengthening: Detailed chemical analysis showing the precise addition of Nitrogen (0.10-0.16%) paired with Chromium (16.00-18.00%) and Nickel (11.00-14.00%) to significantly elevate structural yield point limits without impairing impact toughness.
- Molybdenum-Enhanced Protection: Precise chemical breakdown confirming standard Molybdenum content (2.00-3.00%) to completely arrest localized crevice corrosion and pitting in aggressive chloride boundaries.
- Galling & Hardness Control: Hardness values tracked closely below the maximum standard limit of 233 HBW (95 HRB Rockwell max) to prevent localized galling while maintaining optimal structural load parameters.
- Quality Compliance: 100% visual inspection carried out and verified free from defects and radioactive contamination.
Live Preview: ASTM A194 Grade 8MNA MTC Data
Review the standard parameters and layout before downloading the full document.
TC Number
S49/26-XX
TC Date
25.08.20XX
Material Spec
ASTM A194 Grade 8MNA (AISI 316N Class 1A)
Nut Profile / Size
Heavy Hex Nut / M20
Dimensions / Item
Heavy Hex Nut M20 x 2.5P
Quantity
500.00 NOS
Chemical Composition %
| C | Mn | P | S | Si | Cr | Ni | Mo | N | Fe |
|---|---|---|---|---|---|---|---|---|---|
| 0.054 | 1.52 | 0.032 | 0.012 | 0.46 | 17.20 | 11.45 | 2.25 | 0.128 | Rem |
| Max: 0.080 | Max: 2.000 | Max: 0.045 | Max: 0.030 | Max: 1.000 | Min: 16.00 Max: 18.00 |
Min: 11.00 Max: 14.00 |
Min: 2.00 Max: 3.00 |
Min: 0.10 Max: 0.16 |
Rem |
Mechanical & Hardness Properties
| BRINELL HARDNESS (HBW) | ROCKWELL HARDNESS (HRB) | PROOF LOAD STRESS (MPa) |
|---|---|---|
| 192 | 91 | 530 |
| Max: 233 | Max: 95 | Min: 515 (Heavy Hex Structural Standard) |
Standard References & Compliance
Our processing matrices coordinate directly with severe oil, gas, and structural engineering boundaries. Component evaluation concludes with zero surface flaws or thread variations detected.
| Standard / Requirement | Confirmation on Certificate |
|---|---|
| Visual Inspection | 100% visual inspection carried out & found free from defects. |
| Safety Requirements | Material is certified free from radioactive contamination. |
| Weld Repairs | No weld repairs performed on finished stainless elements. |
| Dimensional Accuracy | All heavy hex sizing verified against standard ASME B18.2.2 requirements. |
Certification Details
We confirm that above mentioned Items was Manufactured, Sampled, Tested and Inspected in accordance with the subjected Customer's Purchase Order and as applicable Drawings, Material Specifications, Codes & Standards and the results of the items have been determined to meet the users' requirements.
Documentation Standard
- EN 10204-2004: 3.1 Certified
- Free from radioactive contamination
- Certified ISO 9001: 2015 Operation
Heat Treatments
- Class 1A Solution Annealed (Post-Machining)
- Liquid Quenched to achieve optimal alloy retention
Testing Conditions
- Hardness limits and proof load tracked at 25°C
- 100% thread path conformance verified
Technical FAQs — ASTM A194 Grade 8MNA MTC Certificate
What specific structural benefits does the inclusion of Nitrogen provide to Grade 8MNA nuts?
The "N" designator in Grade 8MNA highlights a deliberate interstitial addition of Nitrogen (0.10% to 0.16%) to the core austenitic balance (based on AISI 316N). Nitrogen acts as a robust solid-solution strengthener, which substantially raises the minimum yield strength and proof load rating compared to non-nitrogen grades like 8MA, while entirely retaining excellent low-temperature impact ductility.
Why is a post-machining Class 1A solution annealing sequence mandatory for Grade 8MNA?
The "A" suffix establishes Class 1A tracking criteria under ASTM A194 guidelines. Standard Grade 8MN elements can be machined out of bars that were pre-annealed before cold drawing. Conversely, Grade 8MNA heavy hex nuts require a full solution anneal treatment after final machining, drilling, and thread-tapping operations are executed. This fully alleviates residual manufacturing strain and secures complete alloy dissolution, giving the fastener optimized structural protection against environmental stress corrosion cracking (SCC).
Why does this product specification dictate a strict maximum hardness ceiling of 233 HBW?
ASTM A194 limits Grade 8MNA nut hardness to 233 Brinell (95 HRB Rockwell B) to serve as a quality checkpoint verifying that the Class 1A solution annealing process was completely successful. Keeping the material below this threshold preserves its optimized, un-stressed austenitic matrix form, preventing unexpected brittle cracks and reducing localized thread galling risks during high-torque assembly preloads.