Surface-Modified Bainitic Gray Cast Iron Cylinder Liner

Formic acid corrosion resistance

With QPQ or nitriding-oxidizing surface treatments, exhibits significantly reduced corrosion damage compared to untreated liner in formic acid-NaCl media.

Gao, Hao · Wang, Hai-Tao · Zheng, Quan

Materials 2026

Specifications

Mass-loss-equivalent corrosion depth (untreated)

{'zh': '97.65', 'en': '97.65'} μm

Mass-loss-equivalent corrosion depth (untreated)

{'zh': '146.05', 'en': '146.05'} μm

Mass-loss-equivalent corrosion depth (nitriding-oxidizing treated)

{'zh': '55.25', 'en': '55.25'} μm

Mass-loss-equivalent corrosion depth (nitriding-oxidizing treated)

{'zh': '119.00', 'en': '119.00'} μm

Mass-loss-equivalent corrosion depth (QPQ treated)

{'zh': '61.45', 'en': '61.45'} μm

Mass-loss-equivalent corrosion depth (QPQ treated)

{'zh': '112.55', 'en': '112.55'} μm

Mass loss (untreated)

{'zh': '929.8', 'en': '929.8'} mg

Mass loss (untreated)

{'zh': '1391.2', 'en': '1391.2'} mg

Advantages

Corrosion depth greatly reduced

Nitriding-oxidizing treatment reduces mass-loss-equivalent corrosion depth by 43.42% in 5 vol% formic acid-NaCl solution, and still lowers it to 119.00 μm at 10 vol% (untreated 146.05 μm).

Controllable treatment cost

Both nitriding-oxidizing and QPQ are established surface treatment processes that can be applied to existing cylinder liner materials and production lines, offering a corrosion-resistant solution for methanol engines.

Applications

• Methanol engine cylinder liners：Directly replace or modify cylinder liner material to extend liner-piston ring service life in methanol engines
• Corrosion-resistant cast iron components：Provide surface modification solutions for cast iron components resistant to formic acid corrosion
• Surface hardening treatments：Use nitriding-oxidizing or QPQ processes to reduce corrosion rate of cast iron surfaces