Where did it all begin?

Nonstick coatings hit the selling floors in the early 1960s.

The first nonsticks were made primarily of polytetrafluoroethylene (PTFE). PTFE has the lowest coefficient of friction (CoF) of any known solid. In other words, the majority of materials (in this case foodstuffs) do not stick to it.

PTFE's low CoF "releases" the materials, making it easy to separate them from the coating. Therefore, on nonstick pans, most substances are easily removed from the surface.

Unfortunately, PTFE is also very soft and, if unprotected, wears quickly. While early nonsticks had good release, they were soft and wore out after little use. The result: nonstick-coated cookware earned the reputation of being "disposable".
 
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Surface Preparation

Mechanical Cleaning (Grit-Blasting)

The gritblasting process provides the following features:

  • Effectively remove the surface soils
  • Roughen the surface to improve the coating adhesion Remove surface irregularities
  • Remove previous coatings
  • Influences the final appearance of the coated utensil
  • Can be performed on any kind of metal
  • Doesn't require subsequent pre-treatment operations, but requires a degreasing step prior to the gritblast.
  • It's relatively quick
  • Equipment ranges from relatively cheap to moderately expensive.

This pretreatment involves blasting the substrate with a sharp medium. The substrate and application will determine the blast profile required. It is crucial that the parts to be blasted be as clean as possible before blasting, since contamination with dirt or oil not only shortens the life of the blast media, but can also interfere with adhesion. Note: because of labor, this is the most costly method of preparation.

One of the most important benefits of the blasting process is that it helps in the roughening of the surface: a rough surface develops a much larger specific surface compared to a smooth one. A higher surface implies higher adhesion for the coating: this means enhanced adhesion and corrosion resistance for the coating. Gritblasted surfaces are somewhat "activated" and should be coated as soon as possible after the blasting treatment to prevent the oxide layer growth.

Mechanical Cleaning (Grit-Blasting)

The gritblasting process can be evauated by two means:

  • Evenness of the treatment by observation of the piece at glazing angle: the appearance of the surface should be uniform dull grey without glossy spots that indicate poor treatment zones.
  • Surface roughness measurement by means of a profilometer (we recommend a Pocket Mahr Surface Meter): this instrument has a diamond tip that is let sliding on the surface and (just like a phonograph) measures the peaks and the valleys of the profile.

Mechanical Cleaning (Grit-Blasting)

 

 

 
 
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