Ni-Cr-Al-Cu Evanohm Ultra-Precision Resistance Alloy Foil with 0.002-0.05mm Thickness and 5-200mm Width for Aerospace Sensors Featuring Ultra-Low TCR ±2.5 ppm/°C

The Evanohm Ni-Cr-Al-Cu ultra-precision resistance alloy foil represents the highest grade of thin-gauge resistive material available for mission-critical measurement applications. Manufactured to exacting tolerances through vacuum induction melting, controlled cold-rolling, and bright annealing processes, this foil achieves an ultra-low temperature coefficient of resistance of ±2.5 ppm/°C, making it the material of choice for aerospace sensors, metrology-grade reference resistors, and precision medical instrumentation.

Evanohm alloy is a quaternary nickel-chromium-aluminum-copper system with a nominal composition of Ni 74-76%, Cr 19-21%, Al 2-3%, and Cu 1-3%. The synergistic combination of aluminum and copper within the nickel-chromium matrix provides a unique balance of high electrical resistivity, ultra-low TCR, and excellent oxidation resistance. The copper addition contributes to enhanced ductility and improved solderability compared to ternary Ni-Cr-Al alloys. Each melt is produced via vacuum induction melting using high-purity raw materials to ensure minimal trace element contamination and consistent batch-to-batch performance.

Evanohm alloy foils are delivered with a bright, mirror-like surface finish produced through controlled-atmosphere bright annealing. Surface roughness is maintained at Ra ≤0.3 μm, with exceptional flatness suitable for photolithographic patterning of fine-line strain gauge grids. Precision slitting produces clean edges with burr height ≤3% of foil thickness, minimizing stress concentration points and ensuring uniform electrical performance across the full width of the foil.

• Aerospace Sensors: Primary sensing elements for flight control surface load measurement, engine thrust monitoring, structural fatigue sensing, and altitude-compensated pressure transducers
• Metrology and Calibration: Bulk metal foil reference resistors with stability better than 0.01% per year for national standards laboratories and precision instrumentation
• Medical Instrumentation: High-accuracy force sensing in robotic surgical systems, micro-precision infusion pumps, and diagnostic imaging equipment
• Precision Shunts: Current-sensing elements for power management systems, battery monitoring, and energy metering with minimal self-heating error
• Scientific Research: Strain measurement in cryogenic and high-vacuum environments where ultra-stable performance is critical

Every production batch undergoes rigorous quality verification including four-wire resistivity measurement with NIST-traceable standards, full-range TCR characterization from -55°C to +150°C, tensile testing per ASTM E8, scanning electron microscopy for surface inspection, and X-ray fluorescence spectroscopy for composition verification. Certificates of analysis with complete traceability are provided with each shipment. Manufacturing facility maintains ISO 9001:2015 certification and all products comply with RoHS directive requirements.

Foil rolls are individually vacuum-sealed in anti-static barrier bags with humidity indicator cards and desiccant packs. Each roll is wound on a rigid plastic core with interleaving tissue paper to prevent surface marring. Outer packaging consists of reinforced export-grade wooden crates with aluminum foil moisture barrier lining. Custom labeling, private labeling, and neutral packaging options are available upon request. Standard shipment via air freight with full tracking and insurance coverage.