Materials

Mild Steel is used to make around 95% of factory-fitted exhausts. It’s an easy material to work with because it can be bent with a mandrel bender and quickly MIG welded. It is also a cheap material. In aftermarket exhaust manufacture we still sometimes use mild steel for flanges – to keep costs down but usually it is preferred because it is far less likely to warp. The flanges for most applications are 10mm thick which means many years of hassle-free use.

201 is typical of the 200 series of stainless. These steels use manganese to replace nickel in austenitic stainless steels, mainly to ensure lower costs. 201 shares a number of properties with 304 such as corrosion resistance but with some important differences in mechanical properties. Approx. composition – 17% Cr, 6% Mn, 4.5% Ni, 0.10% N. (Composition ranges can vary between EN and ASTM standards).

201 grade combines the following characteristics:

•  Good pitting and crevice corrosion resistance similar to 304
•  Higher strength than 304. 350 MPa minimum 0.2% PS compared to 230 MPa for 304 Stainless.
•  Higher work hardening rate than 304 leading to different forming characteristics.
•  High manganese leads to greater refractory erosion in production.

201 is a typical austenitic manganese bearing stainless steel. The 200 series steels vary greatly depending where in the world they are produced. In India and China for example it is used for kitchen utensils and catering equipment. This is due to the scarcity of nickel in these countries. Europe has a lower usage of 201 Stainless.

304 and its variants are regarded the most common stainless grades in the SSAS database. Approx. composition – 18% CR, 8% Ni. (Composition ranges can vary between EN and ASTM standards).

This grade has the following characteristics:

• Good corrosion resistance
• Good weldability
• Excellent ductility giving stretch formability in pressings
• Hygienic surface
• Work hardening for spring properties
• Ease of manufacture at steel mill

 

Titanium

Titanium is unique as it is around half the weight of stainless steel but, in contrast, it is of course, a lot more expensive. Titanium is perfect for race use, when looking to drop additional weight. All the exhausts we produce can be made in titanium, but you should expect prices to be at least three times more.