Deep Drawing and Stamping with Stainless Steel
Stainless Steels are the ‘easiest’ materials for us to deep draw and stamp. The most common gauge we press is 304, followed by 316. This is because Stainless Steel 304 is less expensive than other alloys, has excellent corrosion resistance, and value. It is very easy to sanitize, which makes it great for kitchen use, medical use, and food applications. Our Stainless Steel 316 gauge products are typically used for chlorine and salt water environments because its properties allow for even better rust and corrosion resistance.
Stainless Steel is graded depending on factors such as its composition, its physical properties, and its applications. Each type of stainless steel is classified by its series number and a numerical grade. Series numbers we typically work with at TMS include 200, 300, and 400.
Well known Stainless Steel properties:
- Corrosion Resistant
- High tensile strength
- More durable than most other sheet metals
- Temperature resistant
- Easy formability
- Easy to use in fabrication
- Low maintenance
- Long lasting
- Attractive appearance
- Environmentally friendly (recyclable)
- Low maintenance
- Low replacement costs
- Capable of being polished
- Can form in different ways – cold-rolling or hot-rolling
- Contains iron
- Contains minimum of 10% chromium
TMS Most commonly Drawn Parts: Vessels, chambers, tanks, receptacles,
enclosures, domes, cups, pans.
Most common markets for our deep drawn parts: Hospitality, Architecture/Furniture, Lighting, and
Automotive
Natural occurring downsides to working with Stainless Steel
- Corrosion: Due to stainless steel’s sensitivity to hydrochloric acids
- Intergranular Corrosion: under intense heat (900-1500 degrees F) the chromium content of stainless steel is removed, the damaged area is recognizable by the presence of a blue and orange stain around the affected area – example is this happens when welding
- Pitting: can occur when the metal is prevented from producing the chromium oxide film that protects it – this results from dirt-build up on the surface that keeps oxygen from reaching the surface and developing this protective film
- Galvanic Corrosion: stainless steel can become corrosive when comes in contact with lead, nickel, copper, copper, and graphite
What is Galling and How do We Avoid it while pressing?
Galling is a wear that happens when two metallic surfaces slide against each other. This is common in press forming, especially deep drawing. The sliding of the metals causes friction and adhesion that can cause the material to transfer between the two surfaces. The result may be very noticeable or can be microscopic. Typically, the result of galling is noticeable and can be fixed by applying more lubricant to the next blank. Stamping dies are commonly made of high-chromium-alloy steel. Since stainless steel shares high chromium levels, it is important to is extremely important to apply the lubricant for the tooling to last as long as possible.
Typical Uses – Part and Current According to the US General Services Administration
- Martensitic stainless steel was originally used for cutlery and munitions in the early 1900s
- Ferritic stainless steel was used for the electric light bulb filament and was commonly used for turbine blades in the early 1900s
- Austenitic stainless steel was developed in 1909 and 1912 and was commonly used as formed sheets in architectural construction
- Austenitic stainless steel = iron-chromium-nickel and iron-chromium-nickel-manganese alloys containing 18% chromium and 8% nickel
- Was manufactured in Great Britain for cutlery, stoves, and motor cars
- In the late 1920s and early 1930s it was marketed for kitchen use, public lobbies, exterior ornament, railings, hardware, doors, light fixtures, furniture, signage, and equipment
- Notable buildings incorporating the use of stainless steel include the Chrysler Building (1930) and the Empire State Building (1931)
- Used for plaques, signs, and sculptural elements
- Used in artwork in many extruded shapes for storefronts, trim, hardware