ASTM A194 GRADE 8S NUTS
ASTM A194 Grade 8S Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Galling-Resistant Austenitic Stainless Steel Fasteners (ASTM A194 Grade 8S / UNS S21800 / Nitronic 60). Verify the fully analyzed chemical composition matrices, carbide solution treatment logs, and mandatory hardness boundaries mapped for heavy-duty structural wear and frictional boundaries.
What's Inside This A194 Grade 8S MTC Certificate
This sample mill test certificate mirrors the thorough quality verification package standard for Carbide Solution Treated high-silicon anti-galling stainless steel nuts shipped from our facility to combat intense cross-surface friction dynamics.
- Full Traceability: Certified under tracking identification TC No.: S53/26-XX, fully mapping back to raw melting heat inputs to secure authentic material continuity.
- Premium Galling Resistance: Detailed analysis showing the accurate integration of Silicon (3.50-4.50%) and Manganese (7.00-9.00%), which provides extraordinary resistance to wear, cavitation, and structural thread freezing under heavy assembly preloads.
- Nitrogen Interstitial Strengthening: Verification logs showing controlled Nitrogen addition (0.08-0.18%) which enhances the baseline design yield strength to nearly double that of regular austenitic 304 fasteners.
- Strict Thermal Controls: Confirms a complete carbide solution annealing treatment followed by rapid cooling to maximize microstructural homogeneity and maintain corrosion resistance.
- Quality Compliance: 100% visual inspection carried out and verified free from defects and radioactive contamination.
Live Preview: ASTM A194 Grade 8S MTC Data
Review the standard parameters and layout before downloading the full document.
TC Number
S53/26-XX
TC Date
14.10.20XX
Material Spec
ASTM A194 Grade 8S (Nitronic 60 Basis)
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 | N | Fe |
|---|---|---|---|---|---|---|---|---|
| 0.065 | 8.15 | 0.024 | 0.008 | 3.92 | 16.85 | 8.40 | 0.138 | Rem |
| Max: 0.100 | Min: 7.00 Max: 9.00 |
Max: 0.060 | Max: 0.030 | Min: 3.50 Max: 4.50 |
Min: 16.00 Max: 18.00 |
Min: 8.00 Max: 9.00 |
Min: 0.08 Max: 0.18 |
Rem |
Mechanical & Hardness Properties
| BRINELL HARDNESS (HBW) | ROCKWELL HARDNESS (HRB / HRC) | PROOF LOAD STRESS (MPa) |
|---|---|---|
| 215 | 91 HRB / 16 HRC | 530 |
| Min: 183 Max: 271 |
Min: 88 HRB Max: 25 HRC |
Min: 515 (Heavy Hex Structural Framework) |
Standard References & Compliance
Our material quality matrices correlate perfectly with high-vibration power generation assemblies, valve internals, and wear-critical oil and gas piping boundaries. Surface testing concludes with zero 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 alloy elements. |
| Dimensional Accuracy | All heavy hex dimensions verified strictly 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 Compliance
- Free from radioactive contamination
- Certified ISO 9001: 2015 Operation
Heat Treatments
- Carbide Solution Treated
- Rapidly liquid quenched to eliminate alloy precipitation
Testing Conditions
- Mechanical proof load and hardness checks performed at 25°C
- 100% thread path conformance verified
Technical FAQs — ASTM A194 Grade 8S MTC Certificate
What specific metallurgical properties make ASTM A194 Grade 8S nuts highly galling-resistant?
ASTM A194 Grade 8S nuts are produced from an advanced nitrogen-and-silicon-modified super austenitic stainless alloy (UNS S21800 / Nitronic 60). Incorporating high concentrations of Silicon (3.50% to 4.50%) and Manganese (7.00% to 9.00%) significantly alters the surface deformation mechanics during high friction contact, preventing cold welding, seizing, and thread freezing without matching coatings or localized lubrication systems.
What differentiates Grade 8S from Grade 8SA fasteners under standard compliance frameworks?
Both grades leverage the exact same chemical formulation base (Nitronic 60 / UNS S21800). However, under ASTM A194 guidelines, Grade 8S parameters require carbide solution treatment on the structural stock or blanks prior to standard final manufacturing. Grade 8SA requires that the final carbide solution heat treatment be completely executed *after* the heavy hex nuts have been fully machined and thread-tapped, entirely resetting any cold work stresses introduced by tapping tools.
Why does this product specification dictate a minimum hardness floor along with a strict maximum ceiling?
Per ASTM A194, Grade 8S nuts carry a strict hardness window of 183 to 271 HBW (88 HRB min to 25 HRC max). The minimum hardness ceiling ensures that the nitrogen interstitial hardening elements remain effective to prevent premature thread stripping under structural preloads. The maximum boundary guarantees that the matrix holds sufficient impact ductility to suppress brittle environment-assisted cracks.