ASTM A194 GRADE 8MA NUTS
ASTM A194 Grade 8MA Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Austenitic Stainless Steel Heavy Hex Nuts (ASTM A194 Grade 8MA). Inspect the exact documentation your QA and engineering teams will receive with every Ananka Fasteners order.
What's Inside This A194 Gr 8MA MTC Certificate
This sample mill test certificate mirrors the rigorous QA documentation package standard for premium corrosion-resistant stainless steel nuts. The "8MA" designation combines the enhanced pitting resistance of Molybdenum-bearing Type 316 stainless steel with a full post-machining solution anneal to remove any residual work-hardening stresses.
- Full Traceability: Certified with TC No.: S316A/26-XX and corresponding ASTM specifications.
- Material Chemistry: Explicitly details the Chromium-Nickel-Molybdenum (16/10/2) chemistry of AISI Type 316 stainless steel, which grants this grade its superior resistance to chlorides and pitting corrosion compared to 304 SS.
- Hardness Verification: Specifically tracks the stringent maximum hardness limit (192 HBW / 90 HRB) mandated for the "A" designation, confirming the nuts are in the dead-soft, fully annealed condition.
- Heat Treatment Tracking: Verifies the essential Carbide Solution Treatment (Solution Annealing) at a minimum of 1900°F (1040°C) performed after threading and machining, followed by a rapid water quench.
- Quality Compliance: 100% visual and dimensional inspection carried out to guarantee perfectly formed threads and flat bearing surfaces in accordance with ASME B18.2.2.
Live Preview: ASTM A194 Grade 8MA Data
Review the standard parameters and layout before downloading the full document.
TC Number
S316A/26-XX
TC Date
22.03.20XX
Material Spec
ASTM A194 GRADE 8MA
Nut Shape / Size
Heavy Hex Nut / M24
Dimensions / Item
Heavy Hex Nut M24-3.0P
Quantity
300.00 NOS
Chemical Composition %
| C | Mn | P | S | Si | Cr | Ni | Mo |
|---|---|---|---|---|---|---|---|
| 0.04 | 1.55 | 0.026 | 0.010 | 0.55 | 16.50 | 10.50 | 2.15 |
| 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 |
Mechanical Properties
| PROOF LOAD STRESS (MPa) | HARDNESS (HBW) |
|---|---|
| 565.40 | 152, 148, 150 |
| Min: 550 | Min: 126 Max: 192 (90 HRB) |
Standard References & Compliance
Our MTC certificates map to the demanding industrial standards for high-temperature and highly corrosive pipeline fasteners. The test reports confirm compliance with As Per ASME/ASTM A194 Grade 8MA with respect to the tests carried out, specifically ensuring final stage heat treatments.
| Standard / Requirement | Confirmation on Certificate |
|---|---|
| Visual Inspection | 100% visual inspection carried out & found free from defects. |
| Safety Requirements | Material is free from radioactive contamination. |
| Weld Repairs | No weld repair performed. |
| Dimensional Accuracy | All dimensions, threads, and bearing surface tolerances conform to ASME B18.2.2. |
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 Standard
- Free from radioactive contamination
- Certified ISO 9001: 2015 Company
Heat Treatments
- Carbide Solution Treated (Annealed)
- Treatment applied after all machining
- Quenching: Rapid Water Quench
Testing Conditions
- Proof load & hardness testing carried at room temperature 25°C
- 100% visual inspection carried out
Technical FAQs — ASTM A194 Grade 8MA MTC Certificate
What does the "A" in Grade 8MA signify?
The "A" suffix indicates that the nuts have been Carbide Solution Treated (fully annealed) after all forming, threading, and machining operations are complete. Standard Grade 8M nuts may retain residual work-hardening from the manufacturing process, allowing a higher hardness (up to 321 HBW). Grade 8MA is kept dead-soft (maximum 192 HBW / 90 HRB).
How does Grade 8MA differ from Grade 8A?
While both are fully solution annealed after machining (hence the "A"), the base alloy is different. Grade 8A uses Type 304 stainless steel, whereas Grade 8MA uses Type 316 stainless steel. Type 316 contains the vital addition of Molybdenum (2-3%), which provides vastly superior resistance to pitting and crevice corrosion, especially in environments exposed to chlorides like seawater or brine.
Why choose Grade 8MA over standard Grade 8M?
The cold-working process used to form threads leaves residual stresses in the metal. In certain harsh chemical environments (like hot chloride solutions), these residual stresses can cause the nut to fail prematurely due to Stress-Corrosion Cracking (SCC). The final solution anneal mandated by the Grade 8MA specification removes these stresses, optimizing the Type 316 alloy for maximum corrosion resistance and longevity.