Pickling Corrosion Inhibitor
A pickling Corrosion Inhibitor slows the attack of pickling acid on the exposed metal and prevents hydrogen embrittlement, increasing the service life of the weld.
Physicochemical Mechanism of Action
A pickling Corrosion Inhibitor is a chemical additive to the pickling acid. It reacts with the exposed metal forming a protective layer that prevents direct contact between the acid and the metal. This interrupts hydrogen ion attack on the metal, slowing embrittlement.
Metallurgical Relevance & Welding Risks
Without a pickling Corrosion Inhibitor, pickling acid can cause rapid hydrogen embrittlement. This can lead to hot cracking and distortion in the weld, compromising joint strength and service life. An Corrosion Inhibitor prevents these adverse effects and ensures a clean etch.
Workshop Practice & Action Guidelines
Use pickling inhibitors in the final pickling acid mixture at a ratio of 1:50 to 1:100. Ensure the Corrosion Inhibitor is fully dissolved and the acid flows well. Check the acid clarity before welding; a milky discoloration indicates excessively high Corrosion Inhibitor concentration. Proper application ensures a stable weld without hot cracking.