Accredited Defensible Chemical Composition Of O/N/H Data at Speed
Inert Gas Fusion (IGF) allows us to quantify oxygen, nitrogen, and hydrogen (ONH Testing) at ppm to percent levels. These elements that drive cleanliness, porosity, toughness, and delayed cracking. AADFW delivers accredited IGF results with expert interpretation and faster turnaround than slow, global labs, keeping critical builds on schedule. Call to get a Quote.
Note: O/N/H are measured by fusion in an inert gas environment. Combustion methods in an environment with oxygen are used for carbon & sulfur determination.
Why ONH Testing Matters
In flight-critical and high-pressure environments, concentration content of O/N/H to determine fatigue life, weld performance, and corrosion/cracking susceptibility.
- Oxygen influences porosity, oxide formation, and ductility, especially in titanium and nickel alloys.
- Nitrogen affects strength/toughness balance, phase stability (e.g., austenite control), and weld metal properties.
- Hydrogen drives embrittlement and delayed cracking, impacting steels, weld overlays, and high-strength fasteners.
Accurate O/N/H data prevents rework and in-service failures, supports WPS/PQR/WPQ, and underpins MRB decisions and OEM/FAA audits.
AADFW’s Approach: Precision, Speed, and Proof
- Accredited & precise: Testing under ISO/IEC 17025 using certified reference materials, matrix-matched calibration, and documented uncertainty.
- Faster results: Streamlined intake, disciplined instrument control, and concise, decision-ready reports compress lead times.
- Trusted by industry: Aerospace and oil & gas teams rely on our traceability, clear acceptance call-outs (when limits provided), and metallurgical context that stands up to audits.
O/N/H by Inert Gas Fusion: What We Test and How We Do It
- Method: High-temperature melting in a graphite crucible under inert carrier gas. Interstitials are released as CO (from O), N₂ (from N), and H₂ (from H) and measured by IR and/or thermal conductivity detectors.
- Matrices: Carbon/low-alloy and stainless steels, titanium, nickel and cobalt superalloys, weld metals, and overlays.
- Sensitivity: Single-ppm to percent levels (instrument- and matrix-dependent). Duplicate runs and control samples confirm lot confidence.
- QA Controls: Daily drift checks, CRMs spanning your decision ranges, blanks, leak checks, and control charts; all retained in quality records.
- Reporting: Results in ppm/% with method notes, calibration/QA summary, and clear spec-limits comparison when provided.
Service Capabilities (Technical Scope)
- Hydrogen (H) Analysis – Detects diffusible/residual hydrogen to manage embrittlement and delayed cracking risk in steels and weldments; valuable for overlays/cladding and high-strength components.
- Nitrogen (N) Analysis – Controls N for strength/toughness balance in steels, phase control in stainless/superalloys, and weld metal property targets.
- Oxygen (O) Analysis – Assesses cleanliness and oxide content to mitigate porosity and ductility loss, critical for Ti/Ni alloys and weld quality.
- Weld & Overlay Interstitial Control – Sampling of weld metal/HAZ to confirm procedure limits and dilution effects for O/N/H.
- Failure & Process Investigations – Pair O/N/H with OES/EDS and metallography to identify contamination sources, oxide scale, or hydrogen pickup.
- Sampling & Preparation – Strict chain-of-custody and heat/part traceability. Small samples of less than 0.3 grams, or thin plates equal or thinner than 0.01 inches that may be punched to obtain small samples are required.
Industries We Support
- Aerospace: Certified O/N/H values for Ti/Ni alloys, weld qualification support, and lot release under OEM/FAA expectations.
- Oil & Gas: Tubulars, pressure components, and weld overlays/cladding for sour/CO₂/subsea service where H and O drive cracking/porosity risk.
- Manufacturing: Mission-critical hardware where interstitial control protects toughness and fatigue life.
Defense: Mission-critical parts where toughness and fatigue life demand high control of H and O composition.
Trusted by engineers and QC managers across mission-critical industries.
Accreditations & Standards Compliance
AADFW operates to ISO/IEC 17025 with traceable calibrations and uncertainty statements. Our IGF testing supports Nadcap-driven program requirements and applicable ASTM/ISO/ASME/AMS methods and chemistry specifications. Reports are audit-ready, with calibration references and QC results available upon request.
Engineer’s Prep Guide: Getting Clean, Defensible O/N/H Numbers
- Keep samples dry & clean: Moisture and oils bias H and O high.
- Minimize surface oxides: Freshly machine; avoid rust/scale and aggressive abrasives that smear.
- Tell us the matrix & limits: We match calibration and QC to your alloy and decision thresholds.
- Specify location: Base vs. weld/HAZ—we’ll sample accordingly and note dilution effects.
- Bundle intelligently: Add for complete gases composition chemistry, OES for alloying elements, and metallography for structure verification.
Why Engineers Choose AADFW
- Accredited & precise IGF methods with CRMs, leak checks, and control charts.
- Faster turnaround to keep qualifications and production gates on time.
- Trusted partner to aerospace and oil & gas QA organizations.
- Expert metallurgists who turn ppm numbers into clear go/no-go decisions—and root-cause guidance when needed.
Call to get a Quote
Control gas concentrations with confidence.
Request a Quote Talk to a Testing Specialist : 817-540-0153
