ASTM A194 GRADE 8MA (AISI 316)
ASTM A194 Grade 8MA Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Molybdenum-Bearing Austenitic Stainless Steel Fasteners (ASTM A194 Grade 8MA / AISI 316). Review the fully analyzed chemical balances, solution annealing tracking parameters, and mechanical limits verified for high-purity, corrosive, and elevated temperature systems.
What's Inside This A194 Grade 8MA MTC Certificate
This sample mill test certificate mirrors the strict QA verification package standard for Class 1A Molybdenum-stabilized AISI 316 stainless steel nuts tracking specialized marine and chemical plant allocations shipped from our facility.
- Full Traceability: Issued under unique tracking identification TC No.: S57/26-XX, fully mapping back to verified melting lot heats.
- Class 1A Solution Treatment: Explicitly confirms that parts have undergone comprehensive solution annealing followed by rapid quenching, where the "A" suffix guarantees structural softening after nut blank fabrication or tapping.
- Molybdenum-Enhanced Chemistry: Detailed chemical breakdown demonstrating critical Molybdenum addition (2.00-3.00%) combined with high Nickel (10.00-14.00%) to completely arrest pitting and crevice corrosion in chloride environments.
- Controlled Structural Hardness: Reports verified mechanical testing limits maintaining maximum Brinell parameters up to 233 HBW (or 95 HRB Rockwell maximum) to protect against joint galling.
- Quality Compliance: 100% visual inspection carried out and verified free from defects and radioactive contamination.
Live Preview: ASTM A194 Grade 8MA MTC Data
Review the standard parameters and layout before downloading the full document.
TC Number
S57/26-XX
TC Date
14.05.20XX
Material Spec
ASTM A194 Grade 8MA (AISI 316 Class 1A)
Nut Profile / Size
Heavy Hex Nut / M20
Dimensions / Item
Heavy Hex Nut M20 x 2.5P
Quantity
750.00 NOS
Chemical Composition %
| C | Mn | P | S | Si | Cr | Ni | Mo | Fe |
|---|---|---|---|---|---|---|---|---|
| 0.045 | 1.62 | 0.031 | 0.011 | 0.54 | 16.85 | 10.20 | 2.15 | Rem |
| Max: 0.08 | Max: 2.00 | Max: 0.045 | Max: 0.030 | Max: 1.00 | Min: 16.00 Max: 18.00 |
Min: 10.00 Max: 14.00 |
Min: 2.00 Max: 3.00 |
Rem |
Mechanical & Hardness Properties
| BRINELL HARDNESS (HBW) | ROCKWELL HARDNESS (HRB) | PROOF LOAD STRESS (MPa) |
|---|---|---|
| 168 | 85 | 525 |
| Max: 233 | Max: 95 | Min: 515 (Heavy Hex Structural Layout) |
Standard References & Compliance
Our documentation profiles map directly to offshore oil, chemical process validation, and severe cryogenic engineering setups. Thread layout evaluation passes with zero surface scaling or defects noted.
| 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 structural elements. |
| Dimensional Accuracy | All heavy hex dimensions verified strictly against standard ASME B18.2.2 parameters. |
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 Compliant
- Free from radioactive contamination
- Certified ISO 9001: 2015 Manufacturing Track
Heat Treatments
- Class 1A Solution Annealed (Post-Machining)
- Liquid Quenched to secure uniform carbide dispersion
Testing Conditions
- Mechanical proof load and hardness logged at 25°C
- 100% thread path conformance verified
Technical FAQs — ASTM A194 Grade 8MA MTC Certificate
What is the definitive purpose of the "A" suffix on Grade 8MA nuts?
The "A" suffix designates a Class 1A processing path. Unlike standard Grade 8M parts which can be solution annealed at the raw bar phase and then cold worked during nut formation, Grade 8MA nuts are mandatory solution annealed after the final forming or machining process. This step relieves all cold forming stresses, lowering the hardness levels and providing optimum resistance to environmental stress corrosion cracking (SCC).
How does Grade 8MA differ from Grade 8A nuts in industrial applications?
Grade 8A nuts are derived from AISI 304 chemistry layouts which lack Molybdenum. Grade 8MA utilizes an AISI 316 stainless steel chemistry foundation, carrying between 2.00% to 3.00% Molybdenum. This element provides vital resistance against localized crevice corrosion and pitting induced by seawater, marine atmospheres, or harsh chemical process streams.
Why is there a maximum hardness constraint of 233 HBW on the product certificate?
ASTM A194 strictly caps Grade 8MA hardness at 233 Brinell (95 HRB Rockwell) to prove the success of the post-machining solution annealing cycle. Keeping hardness below this threshold ensures the austenitic crystal matrix stays fully un-stressed and highly ductile, minimizing the risk of thread galling during high torque preloads.