ASTM A194 GRADE 8CLNA NUTS
ASTM A194 Grade 8CLNA Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Stabilized, Austenitic Stainless Steel Fasteners (ASTM A194 Grade 8CLNA / AISI 347 Class 1A). Review verified chemical distributions, high-temperature stabilization logs, and mechanical compliance profiles engineered for extreme thermal service.
What's Inside This A194 Grade 8CLNA MTC Certificate
This sample mill test certificate mirrors the thorough quality verification package standard for Class 1A post-machining solution-annealed, stabilized austenitic stainless steel heavy hex nuts shipped from our facility to satisfy demanding high-temperature structural parameters.
- Full Traceability: Certified under tracking index TC No.: S65/26-XX, fully correlated with verified mill heat identifiers to guarantee continuous product verification.
- Class 1A Solution Annealing: Explicit verification that components have undergone mandatory solution heat treatment after final machining or thread-tapping operations, successfully relieving micro-stress variables.
- Stabilized Austenitic Chemistry: Detailed analysis showing the precise stabilization with Niobium/Columbium, paired with standard Chromium (17.00-19.00%) and Nickel (9.00-12.00%) matrices to completely mitigate intergranular carbide precipitation across sensitization ranges.
- Mechanical Performance Boundaries: Clear reporting of structural hardness properties maintained safely under the standard maximum of 233 HBW to safeguard against thread galling under high-stress preloads.
- Quality Compliance: 100% visual inspection carried out and verified free from defects and radioactive contamination.
Live Preview: ASTM A194 Grade 8CLNA MTC Data
Review the standard parameters and layout before downloading the full document.
TC Number
S65/26-XX
TC Date
25.08.20XX
Material Spec
ASTM A194 Grade 8CLNA (AISI 347 Class 1A)
Nut Profile / Size
Heavy Hex Nut / M20
Dimensions / Item
Heavy Hex Nut M20 x 2.5P
Quantity
600.00 NOS
Chemical Composition %
| C | Mn | P | S | Si | Cr | Ni | Nb | Fe |
|---|---|---|---|---|---|---|---|---|
| 0.058 | 1.55 | 0.034 | 0.012 | 0.46 | 17.40 | 9.80 | 0.58 | Rem |
| Max: 0.080 | Max: 2.000 | Max: 0.045 | Max: 0.030 | Max: 1.000 | Min: 17.00 Max: 19.00 |
Min: 9.00 Max: 12.00 |
Min: 8xC Max: 1.10 |
Rem |
Mechanical & Hardness Properties
| BRINELL HARDNESS (HBW) | ROCKWELL HARDNESS (HRB) | PROOF LOAD STRESS (MPa) |
|---|---|---|
| 182 | 88 | 530 |
| Max: 233 | Max: 95 | Min: 515 (Heavy Hex Structural Standard) |
Standard References & Compliance
Our material quality records coordinate tightly with mechanical design protocols in chemical process networks and high-load civil structural joints. Thread layout evaluation passes with zero dimensional variances 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 elements. |
| Dimensional Accuracy | All heavy hex sizing verified strictly against ASME B18.2.2 criteria. |
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 Compliance
- Free from radioactive contamination
- Certified ISO 9001: 2015 Manufacturing System
Heat Treatments
- Class 1A Solution Annealed (Post-Machining)
- Liquid Quenched to secure uniform alloy retention
Testing Conditions
- Hardness limits and proof load tracked at 25°C
- 100% thread clearance testing performed
Technical FAQs — ASTM A194 Grade 8CLNA MTC Certificate
What metallurgical benefit does Niobium/Columbium stabilization provide to Grade 8CLNA nuts?
The Grade 8CLNA stabilization (based on AISI 347 chemistry) employs Niobium/Columbium to chemically bond with carbon. This prevents the formation of damaging chromium-rich carbides along the austenitic grain boundaries when the material is subjected to sensitization temperature ranges of 427°C to 816°C (800°F to 1500°F). This stabilization ensures the Chromium remains entirely active within the matrix to maintain peak environmental corrosion resistance.
Why is a post-machining Class 1A solution annealing sequence mandatory for Grade 8CLNA?
The "A" suffix establishes Class 1A tracking criteria under ASTM A194 guidelines. Standard Grade 8CLN fasteners are typically machined from bars that were pre-annealed before cold drawing. Conversely, Grade 8CLNA 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 the specification cap the maximum hardness closely at 233 HBW?
Per ASTM A194 parameters, Grade 8CLNA nuts are certified with a maximum hardness threshold of 233 HBW (or 95 HRB on the Rockwell B scale). Keeping the structural core within this boundary confirms a successful post-machining solution annealing cycle, safeguarding the threads from premature galling or brittle cracking during heavy-duty joint preloads.