A Review on Affordable Corrosion Monitoring Systems and System Development

Steel infrastructure degradation through atmospheric corrosion constitutes a major economic burden, exceeding $ 2.5 trillion globally per year. Conventional monitoring approaches demand sophisticated instrumentation and considerable financial investment, constraining their application to critical high-value assets while leaving widespread conventional infrastructure unmonitored. This work synthesizes current developments in cost-effective corrosion sensing technologies and presents LEROY (Low-cost Electrical Resistance Ohm analYzer), an open-source IoT platform engineered for scalable atmospheric corrosion assessment. Systematic analysis of 90 peer-reviewed studies identifies electrical resistance techniques as the predominant physical measurement approach, representing 25 % of research focus within low-cost corrosion monitoring. Openarchitecture microcontroller platforms, notably Arduino-family systems, have emerged as preferred solutions due to adaptability and network connectivity. Leveraging these insights, LEROY combines precision current sourcing, high-resolution signal conversion, and wireless telemetry in an integrated architecture. Experimental characterization establishes milliohm-resolution measurement fidelity with 0.59 % maximum deviation versus commercial instrumentation. Extended six-month accelerated exposure testing in 3.5 % sodium chloride environment validated continuous metal loss tracking capability, achieving 3.31 % agreement with conventional gravimetric assessment. Measured degradation rates of approximately 60 μ m / year align with ISO 9223 Category C4 corrosivity classification. Substantial cost advantages relative to commercial alternatives combined with IoT-enabled remote access demonstrate feasibility for large-scale sensor deployment across budget-limited infrastructure portfolios, enabling paradigm shift from episodic reactive maintenance toward continuous datainformed asset management.

Keywords: Low-cost sensing technologies; electrical resistance corrosion monitoring; open-source platforms; steel infrastructure; IoT systems.