STAINLESS STEEL – WHY STEEL GRADE TYPE MATTERS!

Unlike most suppliers of steel windows and doors who manufacture their products from 409 stainless steel, Steel Windows and Doors USA offers 304 high grade stainless and 316 marine grade stainless as steel options for the BROMBALL line of windows and doors. So what’s the difference?

What is Stainless Steel?

In general stainless steel is a low-carbon steel that contains approximately 12 percent chromium. This addition of chromium to the steel makes it resist rust and stain less than other types of steel. The addition of nickel content to the steel also enhances its resistance. Chemically speaking, chromium has an element that allows it to produce a filmy texture which helps to prevent against corrosion and even minor scratches and cuts. Consequently, the more chromium which is added to steel directly corresponds to the amount by which the steel is able to resist corrosion and oxidation. Having said this, stainless steel products that turn rusty right away are said to have less chromium content and are most frequently made from Type 409 stainless steel.

Looking at the facts:

Type 304 and 316 stainless steel is commonly more expensive than Type 409 stainless steel due to the fact that it is far more durable and is a much higher quality of stainless steel. Still not convinced? Let’s consult the facts.

     Type 316 Stainless Steel:

• General Properties:
• Type 316 alloy is a molybdenum bearing stainless steel which has excellent corrosion resistance when exposed to a wide range of corrosive environments and media. Consequently, Type 316 stainless has a greater resistance to chemical attack than the 304 and 409 family and is commonly regarded as the “marine grade” stainless steel. Similarly, Type 316 is durable, easy-to-fabricate, clean, weld and finish.

• Chemical Analysis:
• Elements by Percentage by Weight – Maximum Unless Range is Specified.
• C = .08 / Mn = 2.00 / P = .05 / S = .02 / Si = 0.75 / Cr = 16.00 – 18.00 / Ni = 10.00 – 14.00 / Mo = 2.00 – 3.00 / Ti = 0.70

• Mechanical Properties (Room Temperature):
• Yield Strength .2% Proof= 205 (MPa) min / Ultimate Tensile Strength = 515 (MPa) min / Elongation (% in 50mm) = 40 min /  Hardness R = 90 max.

Type 304 Stainless Steel:

• General Properties:
• Type 304 stainless steel It is an aircraft-quality, 16-gauge stainless containing 18 to 20 percent chromium and 8 to 10 percent nickel, also known as austenitic stainless. This means that the material is highly durable and it will never rust. It also has the lightest weight of any of the material grades because of its high chromium content and can meet a wide variety of physical requirements, making them excellent materials for applications including kitchen equipment, hose clamps, springs, truck bodies, exhaust manifolds, stainless atware, storage tanks, pressure vessels and piping.

• Chemical Analysis:
• Elements by Percentage by Weight – Maximum Unless Range is Specified.
• C = .08 / Mn = 2.00 / P = .045 / S = .030 / Si = 0.75 / Cr = 18.00 – 20.00 / Ni = 8.00-12.00 / N = .10

• Mechanical Properties (Room Temperature):
• Yield Strength .2% Proof= 205 (MPa) min / Ultimate Tensile Strength = 515 (MPa) min / Elongation (% in 50mm) = 40 min /  Hardness R = 92 max.

     Type 409 Stainless Steel:

• General Properties:
• Type 409 stainless, also known as ferritic stainless, is a low-carbon steel that is at least 12 percent chromium. It is a rugged and durable material grade offering a variety of finishes from dull “mill” finish to a high-shine finish. In extreme applications and harsh weather conditions, it commonly shows signs of wear, such as surface rust and corrosion. It is often attractive due to its high material selection at a cheaper price.

• Chemical Analysis:
• Elements by Percentage by Weight – Maximum Unless Range is Specified. C = 0.08 / Mn = 1.00 / P = 0.045 / S = 0.030 / Si = 1.00 / Cr = 10.5 – 11.75 / Ni = 0.50 / Ti = 0.75

• Mechanical Properties (Room Temperature):
• Yield Strength 0.2% Proof = 207 (MPa) min / Ultimate Tensile Strength = 380 (MPa) min / Elongation (% in 50mm) = 20 min /  Hardness R = 95 max.

Through persistent innovation and determination, Steel Doors and Windows USA continues to produce the highest quality products available in the industry. With over 40 years of industry experience, Brombal USA shows their true artisanship by specializing in work with the highest quality of steel types, framing materials and finishes in the business. With hundreds of standard and custom colors to choose from, the combination of our high quality steel with a powder coated painted finish is not only a practical solution, but also the perfect choice for unique and elaborate custom designs.