Should I choose carbon steel or stainless steel for shackles and fasteners?
Carbon steel shackles & fasteners have high strength at lower cost. They are available in high grades like 8.8, 10.9. The downside is they rust easily in wet, humid or saltwater environments. They are best for indoor, dry, heavy lifting applications. Stainless steel (SS304 / SS316) has excellent corrosion resistance. It works well outdoors, marine, wet and chemical environments. But stainless steel has lower tensile strength than carbon steel, and price is higher. SS316 performs better than SS304 in salt water. Summary: Carbon steel: high strength, low cost → dry & heavy load Stainless steel: anti-rust → outdoor / marine / corrosive environment
