During the manufacture of stainless steel, an alloy of iron (90%) and chromium (10%), a little of the chromium combines with oxygen from the atmosphere to form a hard oxide coating on the surface. This process continues in a passive form throughout the steel’s life and is what makes it “stainless;” should the finish be removed through corrosion or wear, the metal will no longer be “stainless.” It will rust just like any other steel.
Any contamination of the surface by dirt, or other material, hinders this continual oxidation process and traps corrosive agents, ultimately destroying the metal’s corrosion protection. Therefore, while excessive cleaning cannot wear stainless steel out (just so long as you avoid harsh abrasives), dirt and neglect can damage the steel.
Wash Stainless Steel Regularly
Aguirre suggests cleaning it with a cloth soaked in warm water. Dry it with a towel or cloth to prevent spots caused by minerals in the water. Wipe in the direction of any polish lines. On tougher jobs, you can add a mild detergent to the water without damaging the surface, but always rinse it thoroughly with warm water.
- Brighten a steel sink by polishing with a cloth dipped in vinegar or ammonia, or sprinkle a little baking soda on a sponge, rub the sink gently, and rinse.
- Fingerprints can be removed with glass cleaner or household ammonia. Some newer types of finishes resist fingerprints.
- Cleaners made for stainless steel minimize scratching, remove stains, and polish surfaces.
Use olive oil to remove streaks and undiluted vinegar to clean and polish stainless steel or remove heat stains from cutlery. Club soda also removes streaks and heat stains.
- Take care not to spill dry dishwasher detergent on wet flatware, as this may produce dark spots.
- Rinse off acid, salty foods, or milk and milk products, which tend to corrode the metal, if the flatware or pots are not to be washed soon.
- Avoid discoloration – don’t let pans boil dry or overheat on a burner.
- Stainless steel pans don’t distribute heat evenly; if foods are not stirred while cooking, it tends to stick in “hot spots.”
- Do not use harsh abrasives or steel wool. Remove cooked-on food or grease by using a sponge with:
- A low-abrasion cleaning powder
- A paste of baking soda and water
- A paste of ammonia and rotten stone
- Place a perforated rubber or plastic mats in a stainless steel sink to reduce scratching and marking by pans and tableware.
Repairing Scratches in Stainless Steel
According to the Stainless Steel Information Center, organic solvents can also be used to remove fresh fingerprints and oils and greases that have not had time to oxidize or decompose, the preferred solvent being one that does not contain chlorine. Acetone, methyl alcohol, and mineral spirits are acceptable.
Many commercial cleaners compounded from phosphates, synthetic detergents, or alkalies are available for cleaning severely soiled or stained surfaces. But the fact that a label states “for stainless steel” is not necessarily a guarantee that the product is not abrasive, not acidic, or is low in chloride, so take care.
If the steel has a hairline finish, in which the grain is continuous and runs the length of the surface, scratches may be sanded over with a light grit or pumice; otherwise, scratches should be removed only by a specialist.