
Alloys 309 and 309S are austenitic chromium-nickel stainless steels that are often used for higher temperature applications. Due to their high chromium and nickel content, Alloys 309 and 309S are highly corrosion resistant, have outstanding resistance to oxidation, and excellent heat resistance while providing good strength at room and elevated temperatures. The only significant difference between 309 and 309S is the carbon content. Alloy 309S has a much less carbon composition which minimizes carbide precipitation and improves weldability.
1. Stainless steel 309 coil corrosion resistance:provide excellent corrosion resistance.More resistant to marine atmospheres than Alloy 304.Often used at higher temperatures to take advantage of their oxidation resistance.Have high resistance to sulfite liquors.Generally considered heat resistant alloys.Destructive scaling temperature is approximately 2000oF.Good scaling resistance with regard to continuous and intermittent services.
2.Alloy 309 resists high temperature corrosion in most in-service conditions. Operating temperatures are as follows:
The alloy does not perform as well as Alloy 600 (UNS N06600) or Alloy 800 (UNS N08800) in reducing, nitriding or carburizing atmospheres, but it does outperform most heat resistant stainless steels in these conditions.
3.Cannot be hardened through heat treatment because the consist solely of austenite at room temperature.Higher tensile and yield strengths that can be obtained through cold working and not followed by full annealing are not stable at the higher temperatures where these alloys are used.Creep properties can be negatively affected by the use of cold worked material at these higher temperatures
4.The austenitic class of stainless steels is generally considered to be weldable.Generally considered to have weldability equivalent to the most common alloys of the austenitic class 304 and 304L.Special consideration is needed to compensate for a higher coefficient of thermal expansion to avoid warping and distortion
The packaging of our products (eg. weathered corrugated steel, weathering corrugated steel,corten steel columnl,hot rolled stainless steel plate) ensures that they will not be damaged during transport. For export purposes, the usual export packaging is done in wooden crates or crates. All hr sheet metal, plates and coils are marked with a logo (company mark), grade, size and batch number. On request, we can customise the marking on the product,such as spcc cold rolled steel.
Alloys 309 and 309S are used exclusively for their high temperature oxidation resistance, excellent high temperature strength, along with their resistance to creep deformation and environmental attack. Some examples include, but are not limited to: