Fastener Hardness Testing Services for Aerospace & Oil & Gas 

Prove Case, Core, and Heat-Treat—Accredited Results at Production Speed 

Why Fastener Hardness Testing Matters 

In flight-critical and high-pressure joints, hardness correlates with strength, toughness, hydrogen susceptibility, and fatigue life. For bolts, nuts, screws, pins, and studs, correct hardness at core, case, and thread root is essential to meet ISO 898-1 / ASTM F606/F606M property requirements, validate heat-treat, and prevent failures from decarburization, grinding burn, embrittlement, or plating damage. Traceable hardness data speeds MRB decisions and lot release. 

AADFW’s Approach: Precision, Speed, and Proof 

• Accredited & precise: Testing within an ISO/IEC 17025 quality system using calibrated Rockwell/Brinell/Vickers instruments, verified blocks, and documented uncertainty. 

• Faster results: Dedicated fastener fixtures, efficient sample prep, and right-sized reports compress lead times without compromising rigor. 

• Trusted by engineers: Clear acceptance callouts against drawing/spec limits, heat/lot traceability, and metallurgical interpretation that stands up to audits. 

Fastener Hardness Testing Capabilities

Macro Hardness (Production Conformance) 

• Rockwell HRC/HRB/HRA and Brinell (HBW) on heads, shanks, or sections—scale and load selected by material and geometry. 

• Spot-checks after plating or heat-treat to confirm no over-tempering or surface damage. 

Microhardness & Mapping (Quality of Manufacture) 

• Vickers HV0.3–HV10 / Knoop traverses for case depth (carburized/nitrided) and decarburization at threads and bearing surfaces. 

• Thread root microhardness at the first engaged thread to assess grinding/rolling effects and coating intrusions. 

• HAZ checks on welded or repaired fasteners (as specified). 

Method Control & Reporting 

• Standards: ASTM E18 (Rockwell), ASTM E10 (Brinell), ASTM E384/E92 (microhardness), ASTM E1077 (decarburization by microhardness), with acceptance from ISO 898-1 / ASTM F606/F606M / NASM 1312 as required. 

• Deliverables: Scale, load, dwell, location maps, photos/micrographs, hardness profiles and statistics, acceptance tables (go/no-go), and calibration references—audit-ready. 

Related Integrity Checks (Optional) 

• Metallography: Macro etch for grain flow in heads/forgings; microstructure to assess heat-treat condition. 

• Chemistry: OES for grade verification; C/S and O/N/H for embrittlement/cleanliness risk. 

• Torque–Tension & Prevailing Torque: Correlate hardness to preload performance (ISO 16047, ISO 2320). 

• Hydrogen Embrittlement Support: Coordination with ASTM F519 where specified. 

Industries We Support 

• Aerospace: Hi-Loks®, locknuts, structural bolts, documentation aligned to OEM/FAA expectations. 

• Oil & Gas: Pressure-boundary bolting and subsea hardware where H-pickup and sour service matter. 

• Defense & Advanced Manufacturing: Mission-critical assemblies demanding repeatable preload and certified properties. 
  Trusted by engineers and QC managers across mission-critical industries. 

Accreditations & Standards Compliance

AADFW operates to ISO/IEC 17025 with traceable calibrations, proficiency checks, and uncertainty statements. Testing supports Nadcap-driven program requirements and applicable ASTM/ISO/ASME/NAS fastener standards. Reports are structured for OEM, prime, and regulatory audits. 

Why Engineers Choose AADFW 

• Accredited & audit-ready hardness methods with clear uncertainty and location mapping. 

• Faster turnaround—specialized fixturing and efficient workflows keep gates on schedule. 

• Trusted partner to aerospace and oil & gas QA organizations. 

• Expert metallurgists who convert numbers into clear go/no-go decisions and corrective-action guidance. 

Request a Quote for Fastener Hardness Testing

Confirm property class, case depth, and thread-root integrity with confidence and speed. Request a Quote or Talk to a Testing Specialist : 817-540-0153 to schedule testing today.